If f(x)= x2 + 7; Find x if f(x)= 23

Answers

Answer 1

Answer:

x = 4, -4

Step-by-step explanation:

f(x)= x^2 + 7

f(x) =23

23 = x^2+7

Subtract 7 from each side

23-7 = x^2 +7-7

16 = x^2

Take the square root of each side

±sqrt(16) = sqrt(x^2)

±4 = x


Related Questions

Find the slope of the line that passes through (10, 8) and (1, 4).

Simplify your answer and write it as a proper fraction, improper fraction, or integer.

Answers

2/9 is the slope

Explanation:
8-4 = 4 over 10-1 = 9

Answer:

Step-by-step explanation:

4-8 = -4

1-10 = -9

-4/-9 simplifies to 4/9

A paper clip is just over 4 cm long. How many paper clips like this can be made from a straight piece of wire 10 meters long?

Answers

Answer:

25 Paper Clips

Step-by-step explanation:

100cm is equal to 1 meter. So to find the answer you would need to take the whole of the centimeter (100) and divide that by the paper clips length (4).

100/4 = 25

So, to form a straight line 10 meters long you would need 25 paper clips each 4cm long.

The number of 2,500 paper clips like the given paper clip can be made from a straight piece of wire that is 10 meters long.

What is multiplication?

Multiplication is a type of mathematical operation. The repetition of the same expression types is another aspect of the practice.

For instance, the expression 2 x 3 indicates that 3 has been multiplied by two.

We can start by converting the length of the wire to centimeters since the length of the paper clip is given in centimeters:

10 meters = 10,000 centimeters

To determine the number of paper clips that can be made from the wire, we need to divide the total length of the wire by the length of each paper clip.

Number of paper clips = Total length of wire / Length of each paper clip

Length of each paper clip = 4 cm

Number of paper clips = 10,000 cm / 4 cm

Number of paper clips = 2,500

Therefore, the required number is 2500.

To learn more about multiplication;

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Classify the following triangle. Check all that apply.

Answers

E. and F. it has two congruent sides and has an obtuse angle
E and F: it had an obtuse angle along with 2 congruent sides

Factor the expression below x^2+12+36 A) (x-6)(x-6) B) (x+6)(x+6) C) (x-9)(x-4) D) (x+9)(x+4)

Answers

Answer:

Answer B

Step-by-step explanation:

when you simplify it u get x^2+12+36

Find the area of the triangle. Round your answer to the nearest tenth.
A) 101.3 m^2
B) 58.5 m^2
C) 29.3 m^2
D) 50.7 m^2

Answers

Answer:

A

Step-by-step explanation:

Which of the following reasons can be used to justify statement #3 in the proof?
A Given
B the vertical angel theorem
C the reflexive property of congruence
D SSS​

Answers

c because it is accuet.

hope it helps

Option C . The reflexive property of congruence is the correct reason that can justify statement 3 . BD≅BD

What is the reflexive property of congruence?

The reflexive property of congruence states that every side, every angle, every line segment and every shape is congruent to itself.

To prove that ΔABD is congruent to ΔCBD where given that

1.Line segment AB ≅ Line segment CB  (Given)

2. Then we can write AD ≅CD ; Given : D is the mid point of AC

3. line segment BD ≅ Line segment BD , this is true by reflexive property of congruence which states that every line segment or side is congruent to itself.

BD can be considered as side of both the given triangles

Therefore, the reason that can justify statement 3 is option C.

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How would you describe the curve?

Answers

the answer is C, the curve is a one to one function

The sum of the interior angles of a polygon is 8,100. How many sides does the polygon have?

Answers

Answer:

explanation below

Step-by-step explanation:

(n - 2) * 180 = 8100

n - 2 = 8100/180

n - 2 = 45

n = 45 + 2

n = 47 sides <---answer

happy to help ya :)

An online retail company tracked total number of purchases monthly. In June 2007 they were 4,500 purchases and in September 2008 there were 5,100. The purchases followed a linear model of the form p = S ( t ) = r t + i where p purchases is in 1000's and t is months where January 2007=0

Answers

The linear model for the number of purchases over time is:

p = 0.043t + 3.726

We have,

Let's assign the variable t as the number of months since January 2007, where t = 0 corresponds to January 2007.

Given data:

June 2007: p = 4,500 (in thousands, so p = 4.5)

September 2008: p = 5,100 (in thousands, so p = 5.1)

We can use these data points to set up a system of equations to solve for the slope (r) and the intercept (i) in the linear model p = rt + i.

Using the data points,

4.5 = r(18) + i (June 2007 corresponds to 18 months after January 2007)

5.1 = r(32) + i (September 2008 corresponds to 32 months after January 2007)

Solving this system of equations will give us the values of r and i.

Subtracting the second equation from the first equation:

4.5 - 5.1 = r(18) - r(32)

-0.6 = -14r

r = -0.6 / -14

r = 0.043

Substituting the value of r into one of the equations:

4.5 = 0.043(18) + i

4.5 = 0.774 + i

i = 4.5 - 0.774

i = 3.726

Therefore,

The linear model for the number of purchases over time is:

p = 0.043t + 3.726

Learn more about expressions here:

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The height of the tower is five times the height of the building. If the tower is 52 meter taller than the building.then find the height of the tower

Answers

Answer:

Let, height of the Building = x

Height of the Tower = y

Height of the tower is 5 times from height of the building = y = 5x

Height of the tower is 52 meter taller than the building = y-x = 52

put 5x instead of y in the equation y-x=52

5x-x=52

4x=52

x=52/4

x=13 meter

y=5x

y=5(13)

y=65 meter

Julie went shopping at the mall for a new pair of jeans. She saw a pair at Hollister that was marked $50 with a 40% discount. She saw a pair at Abercrombie that was marked $40 with a 20% discount. How much would each pair of jeans cost after the discount?

Answers

Answer:

30 and 32

Step-by-step explanation:



Which quantity does this number line represent?
A) less than 5
B) less than 4
C) less than 3
D) less than or equal to 4

Answers

D BECAUSE LOOK AT THE TIME LINE

What is your favorite color? A large survey of countries, including the United States, China, Russia, France, Turkey, Kenya, and others, indicated that most people prefer the color blue. In fact, about 24% of the population claim blue as their favorite color.† Suppose a random sample of n = 52 college students were surveyed and r = 12 of them said that blue is their favorite color. Does this information imply that the color preference of all college students is different (either way) from that of the general population? Use α = 0.05. (a) What is the level of significance?

Answers

Answer:

Step-by-step explanation:

We would set up the hypothesis test.

For the null hypothesis,

p = 0.24

For the alternative hypothesis,

p ≠ 0.24

This is a two tailed test

Considering the population proportion, probability of success, p = 0.24

q = probability of failure = 1 - p

q = 1 - 0.24 = 0.76

Considering the sample,

Sample proportion, P = r/n

Where

r = 12

n = 52

P = 12/52 = 0.23

We would determine the test statistic which is the z score

z = (P - p)/√pq/n

z = (0.23 - 0.24)/√(0.24 × 0.76)/52 = - 0.17

Recall, population proportion, P = 0.24

The difference between sample proportion and population proportion(p - P) is 0.24 - 0.23 = 0.01

Since the curve is symmetrical and it is a two tailed test, the p for the left tail is 0.24 - 0.01 = 0.23

the p for the right tail is 0.24 + 0.01 = 0.25

These proportions are lower and higher than the null proportion. Thus, they are evidence in favour of the alternative hypothesis. We will look at the area in both tails. Since it is showing in one tail only, we would double the area

From the normal distribution table, the area below the test z score in the left tail 0.43

We would double this area to include the area in the right tail of z = 0.17 Thus

p = 0.43 × 2 = 0.86

The level of significance is 5%

Since alpha, 0.05 < than the p value, 0.86, then we would fail to reject the null hypothesis. Therefore, at 5% significance level, this information does not imply that the color preference of all college students is different (either way) from that of the general population.

Which of the following ribbon has the greatest cost per inch?

Answers

You didnt give the sizes of the ribbon so let me help you out. You have to divide the size by total cost, bringing you to the cost per one whatever unit you are using.

The equation of the graphed line is..... x+......y=4 ANSWER FAST PLZZXZZ FILL IN THE BLANKS (DOTED LINE)

Answers

Answer:

x+2y=4

Hope this helped

To test the effectiveness of a diet cat food, scientists divided a group of overweight cats into a control and treatment group. The cats in the control group ate their regular food. The cats in the treatment group received a measured portion of diet cat food twice a day. After two months, the cats in the treatment group had lost an average of 1.2 lb, and the cats in the control group had gained an average of 0.1 lb. State the Subjects:

Answers

Answer:

Step-by-step explanation:

The subject in a statistical research work usually refer to the participants involved in the experiment which is usually a quantitative research.

The subjects in this study are all the overweight cats including those in the control and treatment groups.

Find the areas of the sectors formed by ∠DFE. Round your answers to the nearest hundredth.

Answers

Answer:

Area of the sector in red = 177.87 cm²

Area of the sector in blue = 437. cm²

Step-by-step explanation:

Area of the sector = [tex]\frac{\theta}{360}(\pi )(r)^2[/tex]

Area of the sector shaded in blue = [tex]\frac{256}{360}(\pi )(14)^2[/tex]

                                                        = 437.87 cm²

Central angle formed by sector shaded in red = 360 - 256 = 104°

Area of the sector shaded in red = [tex]\frac{104}{360}(\pi )(14)^2[/tex]

                                                      = 177.884

                                                      ≈ 177.88 cm²

Therefore, area of the sector shaded in red = 177.87 cm² and area of the sector in blue = 437.88 cm²

Choco pies are cookies made from chocolate (c), sugar (s), and flour (. Chocolate costs $5 per pound, sugar costs

$3 per pound, and flour costs $2 per pound. You spend $50 on 18 pounds of food and buy twice as much flour as

sugar

Calvin wants to invest $12,000 in deposits. For tax purposes, he wants his total interest to be $600. He wants to put

$1000 more in a 2-year deposit than in a l-year deposit and invest the rest in a 3-year deposit. How much money

should he invest in each deposit?

Number of Years

Rate

2.0%

5.09

6.0%

1-year: $2200, 2-year: $3200, 3-year: $6600

1-year: $4000, 2-year: S5000, 3-year: $3000

1-year: S3200, 2-year: $4200, 3-year: $4600

1-year: $1000, 2-year: S2000, 3-year: $9000

Answers

Question :

justinapace7446

Yesterday

Mathematics

High School

+5 pts

Choco pies are cookies made from chocolate (c), sugar (s), and flour (. Chocolate costs $5 per pound, sugar costs

$3 per pound, and flour costs $2 per pound. You spend $50 on 18 pounds of food and buy twice as much flour as

sugar

Calvin wants to invest $12,000 in deposits. For tax purposes, he wants his total interest to be $600. He wants to put

$1000 more in a 2-year deposit than in a l-year deposit and invest the rest in a 3-year deposit. How much money

should he invest in each deposit?

Number of Years

Rate

2.0%

5.0%

6.0%

Answer:

1-year: $2200, 2-year: $3200, 3-year: $6600

Step-by-step explanation:

Assume y = Amount invested for 1 year.

y + 1000 = investment amount for 2 years

12000 - (y + y + 1000 ) = amount invested for 3 years

11000 - 2y = amount invested for 3 years

Total interest

Multiplying each by its corresponding rate

(0.02 × y) + (0.05 × (y+1000)) + (0.06 × (11000-2y)) = 600

0.02y + 0.05y + 50 + 660 - 0.12y = 600

-0.05y + 710 = 600

-0.05y = 600 - 710

-0.05y = - 110

y = 2200

Therefore first year = y = $2200

Investment for 2 years =y + 1000 = 2200 + 1000 = $3200

Investment for 3 years = 11000 - 2y = (11000 - (2*2200)) = (11000 - 4400) = $6600

An aeroplane covers a distance of 1500km in a certain time at a certain speed.After increasing the speed by 100km/hr, it covers the same distance in a time which is half an hour less than the previous time. Find the previous speed of the aeroplane.
this is from quadratic equations CBSE grade 10
please answer ASAP

Answers

Answer:

previous speed of the aeroplane is 500 km/hr

Step-by-step explanation:

Given: Distance covered by  aeroplane = 1500 km

It covers the same distance in a time which is half an hour less than the previous time if the speed is increased by 100 km/hr

To find: previous speed of the aeroplane

Solution:

Let x denotes the previous speed of the aeroplane.

Time taken by an aeroplane if speed is x km/hr = distance/speed = [tex]\frac{1500}{x}[/tex] hours

If speed is increased by 100 km/hr, new speed = (x + 100) km/hr

Time taken by an aeroplane if speed is (x + 100) km/hr = [tex]\frac{1500}{x+100}[/tex] hours

According to question,

[tex]\frac{1500}{x+100}=\frac{1500}{x}-\frac{1}{2}\\ \frac{1500}{x}-\frac{1500}{x+100}=\frac{1}{2} \\\frac{1}{x}-\frac{1}{x+100}=\frac{1}{3000}\\ \frac{x+100-x}{x(x+100)}=\frac{1}{3000}\\ x^2+100x=300000\\x^2+100x-300000=0\\[/tex]

[tex]x^2+600x-500x-300000=0\\x(x+600)-500(x+600)=0\\(x-500)(x+600)=0\\x=500\,,\,-600[/tex]

As speed can not be negative, [tex]x=-600[/tex] is rejected.

So,

previous speed of the aeroplane is 500 km/hr

Which of the following is a perfect square? 221 196 224 176 Need the answer as quick as possible

Answers

Answer:

196

Step-by-step explanation:

196 is the perfect square number, because its square root is 14.

[tex] \sqrt{196} = 14[/tex]

Q, A fruit seller buys 10 apples for Rs. 45 each from wholesale market .He packs them in a fruit basket for 40 and sells them each for 20 bakets Rs. 600 .Is it loss or gain

Answers

Answer:

It is a gain.

Step-by-step explanation:

CLEAR STATEMENT:

Given that the fruit seller buys 10 apples for 45Rs each from wholesale market.

This implies her buys them for 10 × 45Rs = 450Rs.

UNCLEAR STATEMENT:

He packs them in a fruit basket for 40 and sells them each for 20 baskets Rs. 600.

ASSUMING:

What you are trying to say is that he bought baskets for 40Rs, and sold the apples for 600Rs.

Subtracting his expenses from this value, we have

600Rs - 450Rs - 40Rs = 110Rs

Since this amount is positive, we conclude that it is a gain of 110Rs.

Find the slope of the line 25 points
y
=
9
7
x
+ 1
.

Simplify your answer and write it as a proper fraction, improper fraction, or integer.

Answers

Answer:

97

Step-by-step explanation:

y=mx+b

m= slope

y=97x+1

_____ of the basic trigonometric functions have inverse functions. None, 3, 6, 4

Answers

Answer:

6

Step-by-step explanation:

There are inverses for sine, cosine, tangent, secant, cosecant, and cotangent.

What is the product? Assume x greater-than-or-equal-to 0 (StartRoot 3 x EndRoot + StartRoot 5 EndRoot) (StartRoot 15 x EndRoot + 2 StartRoot 30 EndRoot)

Answers

Answer:

[tex]3\sqrt5 x+ \sqrt x (6 \sqrt{10} +5\sqrt{3}) +10 \sqrt6[/tex]

Step-by-step explanation:

To find the product :

[tex](\sqrt{3x} +\sqrt5)(\sqrt{15x} +2\sqrt{30})[/tex]

[tex]\sqrt{3x}(\sqrt{15x} +2\sqrt{30}) +\sqrt5(\sqrt{15x} +2\sqrt{30})\\\Rightarrow \sqrt{3x}\times \sqrt{15x} +\sqrt{3x}\times 2\sqrt{30} +\sqrt5 \times \sqrt{15x} +\sqrt5\times 2\sqrt{30}\\\Rightarrow \sqrt{45} \times x + 2 \sqrt{90x} + \sqrt{75x} + 2 \sqrt{150}\\\Rightarrow \sqrt{5 \times 9} \times x + 2 \sqrt{9\times 10x} + \sqrt{25 \times 3x} + 2 \sqrt{25 \times 6}\\\Rightarrow 3\sqrt5 x+ 2 \times 3 \sqrt{10x} +5\sqrt{3x} +2 \times 5 \sqrt6\\\Rightarrow 3\sqrt5 x+ 6 \sqrt{10x} +5\sqrt{3x} +10 \sqrt6[/tex]

[tex]\Rightarrow 3\sqrt5 x+ \sqrt x (6 \sqrt{10} +5\sqrt{3}) +10 \sqrt6[/tex]

Some identities used:

1. [tex](a+b)(c+d) = a (c+d) + b(c+d)[/tex]

2. [tex]\sqrt9 =3[/tex]

3. [tex]\sqrt{25} =5[/tex]

4. [tex]\sqrt x \times \sqrt x=x[/tex]

5. [tex]\sqrt a \times \sqrt b = \sqrt{ab}[/tex]

So, the solution is [tex]3\sqrt5 x+ \sqrt x (6 \sqrt{10} +5\sqrt{3}) +10 \sqrt6[/tex]

Answer:it’s b

Step-by-step explanation:

On edge

Expand and Simplify (x+7)(x+5)

Answers

Answer:

[tex]=x^2+12x+35[/tex]

Step-by-step explanation:

[tex]\left(x+7\right)\left(x+5\right)[/tex]

[tex]\mathrm{Apply\:FOIL\:method}:\quad \left(a+b\right)\left(c+d\right)=ac+ad+bc+bd[/tex]

[tex]a=x,\:b=7,\:c=x,\:d=5\\=xx+x\cdot \:5+7x+7\cdot \:5\\=xx+5x+7x+7\cdot \:5\\=x^2+12x+35[/tex]

x^2+5x+7x+35
and then final simplified answer is going to be x^2+12x+35

Solve 5 + x - 14 = x - 7

Answers

Answer:

No solution

Step-by-step explanation:

5+x-14=x-7

-9+x=x-7

2+x=x

2=0

No solution

part 4. Find the missing sides for the 30 60 90 triangles. Please show work for each​

Answers

10. tan(30) = l / 6√3

l = tan(30) x 6√3

l = 6

cos(30) = 6√3 / y

y =  6√3/cos(30)

y = 12

11. tan(30) = c/30

c = 30 x tan(30)

c = 10√3

cos(30) = 27/w

w = 27/cos(30)

w = 18√3

12.

sin(60) = 36/y

y = 36/sin(60)

y = 24√3

tan(60) = 36/x

x = 36/tan(60)

x = 12√3

Answer:

  10. (l, y) = (6, 12)

  11. (c, w) = (9√3, 18√3)

  12. (x, y) = (12√3, 24√3)

Step-by-step explanation:

Side ratios, shortest to longest, in a 30°-60°-90° triangle are ...

  1 : √3 : 2

__

10. l : 6√3 : y = 1 : √3 : 2

multiply by 6

  = 6 : 6√3 : 12

  l = 6, y = 12

__

11. c : 27 : w = 1 : √3 : 2

multiply by 27/√3 = 9√3

  = 9√3 : 27 : 18√3

  c = 9√3, w = 18√3

__

12. x : 36 : y = 1 : √3 : 2

multiply by 36/√3 = 12√3

  = 12√3 : 36 : 24√3

  x = 12√3, y = 24√3

__

This is easier when the triangle is drawn to clearly differentiate the lengths of the sides. The long leg is opposite the 60° angle; the short leg is opposite the 30° angle.

3x+4+3=40 i need help very fast

Answers

Answer:

x = 11

Step-by-step explanation:

Answer:

x = 11

Step-by-step explanation:

3x11 = 33

4+3 = 7

33 + 7 = 40

3. Shenker has 45 CDs.
He gives 10 CDs to his brother.
a) Write an equation you can solve to find how many CDs
Shenker has left.
b) Solve the equation.

Answers

Answer: The equation is 45-10=x the answer is 35

Step-by-step explanation: To make the equation you need to have and = sign so, we can do what he has (45) and subtract what he gives away (10) which would equal what he has left (x)

Answer:

45 (initial amount) - 10 (given to brother) = x (number of cd's left)

Equation:

    45 - 10 = x

Answer:

    35 CDs

Help will mark brainliest

Answers

Answer:

- 1 4/5

Step-by-step explanation:

-1 1/5 + - 3/5

Since the signs are the same, we add and take the sign

1 1/5 + 3/5

1 4/5

The sign is negative

- 1 4/5

On the number line start at - 1 1/5 and go to the left 3/5( since the sign is negative)  you will end up at - 1 4/5

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These five concepts provide a modem interpretation of Mendelian postulates. - Inheritance is governed by information stored in discrete factors called genes. - Genes are transmitted from generation to generation on vehicles called chromosomes. - Chromosomes, which exist in pairs in diploid organisms, provide the basis of biparental inheritance. - During gamete formation, chromosomes are distributed according to postulates first described by Gregor Mendel, based on his nineteenth-century research with the garden pea. - Mendelian postulates prescribe that homologous chromosomes segregate from one another and assort independently with other segregating homologous during gamete formation. Based on these concepts, choose statements that correlate Mendel's four postulates with what is now known about genes, alleles, and homologous chromosomes. Select the five correct statements. a. 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