Solve each system by substitution
Y=-2x+4
y=-3x+3

Answer:

  236 in²

Step-by-step explanation:

You want the surface area of the figure comprised of two cuboids.

The surface area of the figure will be the sum of the total surface area of the purple cuboid, plus the lateral surface area of the yellow cuboid.

  SA = 2(LW +H(L +W)) + Ph

  SA = 2(9·4 +2(9 +4)) +(4·4)(7) = 236 . . . . square inches

The surface area of the composite figure is 236 square inches.

__

Additional comment

You can consider the face on the right side to be equal in area to the area of the purple cuboid that is covered by the yellow one. So, figuring the total area of the purple cuboid effectively includes the area of the face on the right side.

Then the remaining part of the area of the yellow cuboid is the area of the four 7×4 rectangles that are its lateral area.

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Answer:

a) y=0.50x+15  

b) The graph of this equation form on a coordinate plane is a line.

c) Slope  =0.50 and y-intercept = 15

Step-by-step explanation:

Let x = Number of miles driven by car

Given: The cost of renting a car for a day is $0.50 per mile plus a $15 flat fee.

a) Total cost = 0.50x+15

If y =total cost of renting the car, then y=0.50x+15   (i)

b) Above equation is similar to y= mx+c  (ii) [m = slope , xc=y-intercept] which a linear equation .

So the graph of this equation form on a coordinate plane is a line.

c) Comparing (i) and (ii)

m=0.50 , c=15

Hope this helps :)

The article red was titled "sense of emotion of dog and cat to humans"

To visualize the differences in feeling between Dogs and cats towards people, I would think of a dog swaying its tail and hopping up with fervor upon seeing its owner, whereas a cat may approach its owner more calmly and gradually with a loose tail.

I might picture the puppy gasping and looking for physical fondness, whereas the cat may lean toward to be petted or rubbed under the chin.

Dogs show enthusiasm and affection towards owners, while cats exhibit different behaviors. Dogs show excitement through body language like wagging tails, jumping, seeking affection, and vocalizing.

Pets express joy and eagerness to be around humans, with cats being more reserved towards humans. Although affectionate, cats express emotions subtly such as calm body posture and soft chirping.

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True, The more variables that are deployed to segment a market, the more useful is the resulting segmentation likely to be.

We have,

The factors which are be used to member a request are the segmentation variables. Common variables include demographic, geographic, psychographics and behavioral considerations.

Quantifiable population characteristics, similar as age, gender, income, education, family situation.

The primary ideal of segmentation is to identify guests with analogous attributes, and to find which parts of guests that are seductive from a profit perspective.

Understanding the request segmentation allows marketers to produce a more effective and effective marketing blend.

Hence, True, The more variables that are deployed to segment a market, the more useful is the resulting segmentation likely to be.

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complete question:

The more variables that are deployed to segment a market, the more useful is the resulting segmentation likely ot be.[See p.104]Group of answer choicesTrueFalse

Answer:

A = P(1 + r/n)^(n*t) is the formula

Where:

A = the account balance after t years

P = the principal amount (initial investment)

r = the annual interest rate (as a decimal)

n = the number of times the interest is compounded per year

t = the time in years

P = $6,154

r = 0.08 (8% expressed as a decimal)

n = 52 (compounded weekly)

t = 10

A = 6154(1 + 0.08/52)^(52*10)

A ≈ $14,239.44

Therefore, the account balance after 10 years will be approximately $14,239.44.

(a) The 92% CI for overall proportion of pudding packs containing less than 3.25oz of pudding at α = 0.08 is (0.5806, 0.6994);

(b) The 99% CI for overall proportion of pudding packs containing more than 3.25oz of pudding at α = 0.01 is (0.2726, 0.4474).

Part (a) : To construct a confidence-interval for the overall proportion of pudding packs containing less than 3.25oz of pudding, we use the following formula : CI = p' ± [tex]z_{\frac{\alpha}{2} }[/tex] × √(p'(1-p')/n);

where p' is = sample proportion, [tex]z_{\frac{\alpha}{2} }[/tex]  is = critical z-value for the desired confidence level, and n is = sample size.

In this case, p' = (200-72)/200 = 128/200 = 0.64, the sample size is n = 200, and

We know that the critical z-value for a 92% confidence interval(α = 0.08) is approximately 1.75;

Substituting the values,

We get,

CI = 0.64 ± 1.75 × √(0.64(1 - 0.64)/200)

CI = 0.64 ± 0.059421;

CI = (0.5806, 0.6994);

Therefore, the required confidence interval is (0.5806, 0.6994).

Part (b) : In this case, p' = 72/200 = 0.36, the sample-size is n = 200, and

We know that the critical z-value for a 99% confidence interval (α = 0.01) is approximately 2.57;

Substituting the values,

We get,

CI = 0.36 ± 2..57 × √(0.36(1 - 0.36)/200)

CI = 0.36 ± 0.087426;

CI = (0.2726, 0.4474);

Therefore, the required confidence interval is (0.2726, 0.4474).

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Answer:

The area of the largest square is 289 square units, because it is the sum of areas of the two smaller squares, 64 square units and 225 square units.

Step-by-step explanation: JUST PASSED IT ON STUDY ISLAND 100% CORRECT ANSWER

The marginal profit in dollars for the sale of expensive watches when approximately $1912.61.

Find the marginal profit in dollars from the sale?

We need to find the marginal profit in dollars from the sale of x expensive watches for the given profit function P(x) = 0.08x² - 5x + 6x^0.2 - 5200 when (a) x = 300, (b) x = 2000, (c) x = 5000, and (d) x = 12,000.

Find the derivative of the profit function P(x), which represents the marginal profit.
P'(x) = dP(x)/dx = 0.16x - 5 + (6 * 0.2 * x^(-0.8))

Calculate the marginal profit for each specified value of x:

x = 300:
P'(300) = 0.16(300) - 5 + (6 * 0.2 * 300^(-0.8)) ≈ 42.57

x = 2000:
P'(2000) = 0.16(2000) - 5 + (6 * 0.2 * 2000^(-0.8)) ≈ 317.52

x = 5000:
P'(5000) = 0.16(5000) - 5 + (6 * 0.2 * 5000^(-0.8)) ≈ 794.57

x = 12,000:
P'(12,000) = 0.16(12,000) - 5 + (6 * 0.2 * 12,000^(-0.8)) ≈ 1912.61

So, the marginal profit in dollars for the sale of expensive watches when (a) x = 300 is approximately $42.57, (b) x = 2000 is approximately $317.52, (c) x = 5000 is approximately $794.57, and (d) x = 12,000 is approximately $1912.61.

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To find the general expression for the elasticity of demand (e_p), we need to differentiate the demand function with respect to price (p) and multiply it by the ratio of price to quantity (p/q). The elasticity of demand measures the responsiveness of quantity demanded to changes in price.

The general expression for elasticity of demand (e_p) can be calculated as:

e_p = (dQ/dp) * (p/Q)

Where dQ/dp represents the derivative of the demand function with respect to price, and Q represents the quantity demanded.

The elasticity of demand helps us understand how sensitive the quantity demanded is to changes in price. If e_p is greater than 1, demand is considered elastic, meaning that quantity demanded is highly responsive to price changes. If e_p is less than 1, demand is inelastic, indicating that quantity demanded is less responsive to price changes.

In conclusion, the general expression for the elasticity of demand (e_p) is calculated by taking the derivative of the demand function with respect to price and multiplying it by the ratio of price to quantity. This measure helps determine the responsiveness of quantity demanded to changes in price.

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Answer:

The first box and whisker plot

Step-by-step explanation:

A box and whisker plot gives you the five number summary for a set of data.  The five number summary is

Maximum and minimum:

We know from the data that the minimum value is 100 and the maximum value is 200.  However, because both boxes available as answer choices have the correct minimum and maximum, we'll need to find more data.

Median:

We can start finding the median first by arranging the data from the least to greatest.  Then, we find the middle of the data.  Because there are 9 points and 9 is odd, we know that there will be 4 points to the left of the median and 4 points to the right of the median:

100, 100, 120, 120, 150, 165, 180, 180, 200

150 has 4 numbers both on its left and right sides so its the median.

Because both of the plots available as answer choices have the correct median, we we'll need to find more data.

First Quartile/Q1:

In order to find Q1, we must find the middle number of the four numbers to the left of the median.

Because we have an even number of points, we will get two middle numbers, 100 and 120.  To find the middle of all four points, we average these two numbers:

(100 + 120) / 2 = 220 / 2 = 110

Only the first box has the accurate Q1 value, so it's our answer.

We don't have to find Q3, since both boxes have the correct Q3, but only the first box has the correct minimum, correct Q1, correct median, correct Q3, correct maximum.

The value of the velocity, u is 19.6 m/s.

The greatest height reached by the particle is 19.6 m.

The total time during which the particle is at a height greater than half its greatest height is 2.33 s.

a) To find the value of the velocity, u, we can use the formula for the time of flight of a vertically projected particle:

t = 2u/g

Since the particle returns to the same point after 4 seconds, we have:

2t = 4

Substituting the value of t in the first equation, we get:

u = gt/2 = 9.8 x 2

u = 19.6 m/s

b) To find the greatest height reached by the particle, we can use the formula for the maximum height reached by a vertically projected particle:

h = u^2/2g

Substituting the value of u, we get:

h = 19.6^2/(2 x 9.8)

h = 19.6 m

c) To find the total time during which the particle is at a height greater than half its greatest height, we can first find the height at which the particle is at half its greatest height:

h/2 = (u^2/2g)/2 = u^2/4g

Substituting the value of u, we get:

h/2 = 19.6^2/(4 x 9.8) = 24.01 m

So, the particle is at a height greater than half its greatest height when it is above 24.01 m.

Next, we can find the time taken by the particle to reach this height:

h = ut - (1/2)gt^2

24.01 = 19.6t - (1/2)9.8t^2

Solving this quadratic equation, we get:

t = 2.33 s or t = 4.10 s

The particle takes 2.33 s to reach a height of 24.01 m, and it takes another 1.67 s (4 - 2.33) to return to the ground.

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Points a,b and c satisfied the Pythagoras theorem. Thus, the triangle abc is a right angled triangle.

Every triangle has inner angles that add up to 180 degrees. A right angle and a right triangle are both formed when one of their internal angles is 90 degrees.

Given coordinates :

a(5,2) , b(2,-3) and c(-8,3).

Find the distance between the points using the distance formula:

d = √[(x2 - x1)² + (y2 - y1)²]

ab = √[(2 - 5)² + (- 3 - 2)²]

ab = √[(-3)² + (- 5)²]

ab = √[9 + 25]

ab = √34

ab² = 34

bc = √[(2 + 8)² + (- 3 - 3)²]

bc  = √[(10)² + (- 6)²]

bc  = √[100 + 36]

bc  = √136

bc²  = 136

ac = √[(-8 - 5)² + (3 - 2)²]

ac = √[(-13)² + (1)²]

ac = √[169 + 1]

ac = √170

ac² = 170

Now,

(ac)² = (bc)² + (ab)²

170 = 136 + 24

170 = 170

This, points a,b and c satisfied the Pythagoras theorem. Thus, the triangle abc is a right angled triangle.

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The sum of the first 10 terms of the given series  8,20/3,50/9... is 140.

Given series: 8,20/3,50/9...

The given series is not in a standard form, but it appears to be an arithmetic sequence with a common difference of  4/3. To check this, we can find the difference between consecutive terms:

20/3-8=4/3

50/9-20/3=4/3

Thus, the common difference is indeed [tex]\frac{4}{3}[/tex].

We notice that each term of the series can be written as:

a_n=a+(n-1)d

a_n=8+(n-1)(4/3)

where n is the index of the term, and 4/3  is the common difference between the consecutive terms.

To find the sum of the first 10 terms of the series, we use the formula for the sum of an arithmetic series:

S=(n/2)[2a_1+(n-1)d]

where S is the sum of the series, a_1 is the first term of the series, d is the common difference, and n is the number of terms to be added.

Substituting the given values, we get:

S=(10/2)[2*8+(10-1)(4/3)]

Simplifying the expression:

S=5[16+9(4/3)]

S=5[16+12]=5(28)=140

Therefore, the sum of the first 10 terms of the series is 140.

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Sophie will pay money equivalent to $100 for 15m at the same store.

The term "money" in mathematics refers to a form of payment, such as bills, coins, and demand deposits, that is used to purchase goods and services. Money is used to pay for the worth or price of an item or service.

A country's monetary system is referred to as its currency.

In the case of Gareth,

Money paid for 9 m of climbing [tex]=\$60[/tex]

Money paid per m of climbing [tex]=\$60\div9[/tex]

Thus, money paid by Sophie for 15 m of climbing [tex]= 15 \times (60\div9)[/tex]

[tex]\boxed{\bold{= \$100}}[/tex]

Hence Sophie will pay money equivalent to $100 for 15m at the same store.

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Answer:

$100

Step-by-step explanation:

We know that for 9m of rope, Gareth had to pay $60.

The question is asking us to find out how much Sophie will pay for 15m of rope.  To do this, we have to find out how much is paid per meter of rope.

[tex]60/9\\=6\frac{2}{3}[/tex]

For the sake of not using fractions, let's keep it as an improper fraction: 60/9

So, we can write an equation for the price of 15m of rope:

(60/9)·15

=100

So, Sophie will pay $100 for 15m of rope.

Hope this helps! :)

Answer: 20 kg

Step-by-step explanation:

You follow the line of best fit until 50cm

Then you trace across and look at the x-axis.

There you will find that the dog will be 20kg at 50cm using the line of best fit.

Answer:

x - 5y

Step-by-step explanation:

6x - 8y - 5x + 3y =

= 6x - 5x - 8y + 3y

= x - 5y

Answer:

1x + 11y

Step-by-step explanation:

Answer:

There are 16 total outcomes for tossing 4 quarters

This is because each coin flip has 2 possibilities, so if you flip the coin 4 times it will equal

2x2x2x2.

The surface area of Dante's tent is approximately 180 square feet.

To find the surface area of Dante's tent, we need to find the area of each of its faces and then add them up. Since the tent is in the shape of a triangular prism, it has three rectangular faces and two triangular faces.

First, let's find the area of each rectangular face. We know that the tent is 8 feet long and 4.3 feet tall. To find the width of each face, we need to use the Pythagorean theorem since the base of the tent is equilateral. So, we can use a triangle with sides of 5 feet (the base of the tent) and 4.3 feet (the height of the triangular face) to find the width of each rectangular face.

a^2 + b^2 = c^2
5^2 + 4.3^2 = c^2
25 + 18.49 = c^2
43.49 = c^2
c = √43.49
c ≈ 6.6 feet

Now that we know the width of each rectangular face, we can find the area of each face:

Area of rectangular face = length x width
Area of rectangular face = 8 x 6.6
Area of rectangular face ≈ 52.8 square feet

Next, let's find the area of each triangular face. Since the base of the tent is equilateral, each triangular face has a base of 5 feet and a height of 4.3 feet. The area of each triangular face is:

Area of triangular face = (base x height) / 2
Area of triangular face = (5 x 4.3) / 2
Area of triangular face ≈ 10.8 square feet

Now we can add up the areas of all five faces to find the total surface area of the tent:

Surface area of tent = 3 x area of rectangular face + 2 x area of triangular face
Surface area of tent = 3 x 52.8 + 2 x 10.8
Surface area of tent = 158.4 + 21.6
Surface area of tent ≈ 180 square feet

Therefore, the surface area of Dante's tent is approximately 180 square feet.

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When the parallelogram, diagonals bs and et bisect at each other at o, we get the following answers:

1. In a parallelogram, the diagonals bisect each other. So, if ES = 10 cm, then EO = OS = 5 cm. Since EO and OS are half of the diagonal ET, then ET = EO + OS = 5 cm + 5 cm = 10 cm. Similarly, diagonal BT will also be equal to 10 cm, as it has the same length as diagonal ET.

2. In a parallelogram, opposite sides are equal. So, if BE = 13 cm, then TS = 13 cm, as they are opposite sides.

3. If EO = 6 cm and SO = 7 cm, then the length of diagonal ET is EO + OS = 6 cm + 7 cm = 13 cm. Since the diagonals of a parallelogram are equal, the length of diagonal BS will also be 13 cm.

4. If ET + BS = 18 cm and SO = 5 cm, we can use the fact that diagonals bisect each other to find ET and BS. Let EO = x cm. Then, ET = 2x cm and BS = 2(5-x) cm. Now, we can set up the equation: 2x + 2(5-x) = 18. Solving for x, we get x = 4 cm. So, ET = 2x = 8 cm and BS = 2(5-x) = 10 cm.

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Each portion of Grace weighs 1/8 pound.

It gauges how much gravity is pulling on a body.

If Robert has 3/4 pound of Grace and he wants to divide it into six equal portions, we can find the weight of each portion by dividing 3/4 by 6:

(3/4) / 6 = (3/4) * (1/6) = 1/8

So each portion of Grace weighs 1/8 pound.

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In this scenario, the sampling units are four households, the variable of interest is the average food cost, and auxiliary information associated with the units is the number of people in each household and total food cost.

Sampling Units: The sampling units are the four households selected from the 25,000 households in the population.

They are as follows:

1. Household with 4 people that spent $150 on food

2. Household with 2 people that spent $100 on food

3. Household with 4 people that spent $200 on food

4. Household with 3 people that spent $140 on food

Variable of Interest: The variable of interest is the average cost on food per household for a week.

Auxiliary Information: The auxiliary information associated with the units includes the number of people in each household and the total amount spent on food for that week.

To estimate the average cost on food per household for a week, follow these steps:

1. Calculate the total cost on food for all four households: $150 + $100 + $200 + $140 = $590

2. Divide the total cost by the number of households: $590 / 4 = $147.50

So, the estimated average cost on food per household for a week is $147.50.

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The general solution to the given differential equation:

[tex]y = (9x + C)e^(-6x)[/tex]

To solve the given differential equation, dy + 6ydx = 9e^(-6x)dx, we can first rewrite it as a first-order linear differential equation:

[tex]dy/dx + 6y = 9e^(-6x)[/tex]

Now, we will find the integrating factor, which is e^(∫P(x)dx), where P(x) is the coefficient of y in the equation:

Integrating factor =[tex]e^(∫6dx) = e^(6x)[/tex]

Next, we multiply the entire differential equation by the integrating factor:

[tex]e^(6x)(dy/dx + 6y) = 9e^(-6x)e^(6x)[/tex]

This simplifies to:

[tex]e^(6x)(dy/dx) + 6e^(6x)y = 9[/tex]

Now, the left side of the equation is the derivative of the product of y and the integrating factor:
[tex]d/dx(y * e^(6x)) = 9[/tex]

To solve for y, integrate both sides with respect to x:

[tex]∫[d/dx(y * e^(6x))]dx = ∫9dx[/tex]

This results in:

[tex]y * e^(6x) = 9x + C[/tex]

Finally, we solve for y by dividing by e^(6x):

[tex]y = (9x + C)e^(-6x)[/tex]

And that is the general solution to the given differential equation.

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Answer: C

Step-by-step explanation: after rotating, if you split it in half horizontally, you have two cones

The three-dimensional figure formed when the triangle is rotated around the dashed line through B and C is a cone.

A cone is a three-dimensional geometric form with a flat base and a smooth, tapering apex or vertex. A cone is made up of a collection of line segments, half-lines, or lines that link the base's points to the apex, which is a common point on a plane that does not include the base.

When we rotate a two-dimensional shape around an axis, we create a three-dimensional solid. This process is known as "revolution" or "rotational symmetry".

In this particular case, we have a triangle that can be rotated around the line segment that connects points B and C. If we were to rotate the triangle around this axis, we would create a three-dimensional solid. To figure out what kind of solid this is, we can think about the cross-sections that would be created if we were to slice through the solid perpendicular to the axis of rotation.

If we were to slice through the solid perpendicular to the axis of rotation, we would get a circle. This means that the solid created by rotating the triangle is a cylinder.

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Answer:

31.33 degrees

Step-by-step explanation:

The question is asking to find angle x.  You can use sine to find out x because sine is opposite/hypotenuse but since you are finding an angle measurement, it would be to the power of -1.  So:

sine^-1=13/25

31.33

To find the revenue function, we need to multiply the price (p) by the quantity sold (x). The price function given is p = 5,300 - dollars, so we can substitute this into our revenue function as follows:

Revenue = p * x
Revenue = (5,300 - dollars) * x

We also know that production is limited to 100 units, so we need to take that into account when determining the revenue function. If x is greater than 100, then the revenue will be limited to 100 units sold. If x is less than or equal to 100, then the revenue will be based on the actual quantity sold.

To incorporate this constraint into our revenue function, we can use a piecewise function:

Revenue = { (5,300 - dollars) * 100           if x > 100
             (5,300 - dollars) * x             if x <= 100 }

Simplifying the piecewise function, we get:

Revenue = { 530,000 - (dollars * 100)        if x > 100
             (5,300 - dollars) * x             if x <= 100 }

Therefore, the revenue function for this monopoly is:

Revenue = { 530,000 - 100 * dollars        if x > 100
             (5,300 - dollars) * x             if x <= 100 }
Hi! To find the revenue function, we first need to determine the total revenue, which is the product of the price per unit (p) and the number of units sold (x). Given the demand function p = 5,300 - x dollars and the average cost function C = 3,010 + 2x dollars, we can find the revenue function as follows:

Revenue function, R(x) = p * x
R(x) = (5,300 - x) * x

By simplifying the equation, we get:
R(x) = 5,300x - x^2

So, the revenue function for this monopoly is R(x) = 5,300x - x^2.

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If you select a marble without looking and then put it back if you do this 90 times, the probability of selecting an orange or a pink marble on any given trial is 1/2 or 0.5.

If you select a marble without looking and then put it back, the probability of selecting any particular marble on any given trial is the same for all marbles. Assuming there are only two possible outcomes - selecting an orange marble or a pink marble - the probability of selecting an orange or a pink marble on any given trial is 1/2 or 0.5.

Since the probability of selecting an orange or a pink marble on each trial is the same, the best prediction for the number of times you will select an orange or a pink marble out of 90 trials is an equal number of times for each color. Therefore, the best prediction for the number of times you will select an orange or a pink marble is 45 times each.

This is only a prediction based on probability, and the actual number of times you select an orange or a pink marble may differ from the prediction due to chance. However, over a large number of trials, the actual outcomes should approach the predicted probabilities.

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2/5 of the packages weighed more than 1 2/5 pounds.

To find the fraction of packages that weighed more than 1 2/5 pounds, we need to count the number of packages that weighed more than 1 2/5 pounds and divide it by the total number of packages.

There are a total of 10 packages. Out of these, we can see that 4 packages weighed more than 1 2/5 pounds: 1 1/5, 1 3/5, 1 3/5, and 1 4/5.

Therefore, the fraction of packages that weighed more than 1 2/5 pounds is:

4/10

This can be simplified to:

2/5

Hence, only 2/5 of the package weighed more.

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The expression that is equivalent to 1/4(8 - 6x + 12) is 2 - 3x/2 + 6

Algebraic expressions are simply defined as those mathematical expressions that are composed of terms, variables, their coefficients, their factors and constants.

These mathematical expressions are also comprised of arithmetic operations.

These operations are listed thus;

From the information given, we have that;

1/4(8 - 6x + 12)

expand the bracket, we have;

8 - 6x + 12/4

Divide in group, we have;

8/4 - 6x/4 + 12/4

Divide the values

2 - 3x/2 + 6

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