A 56 kg diver runs and dives from the edge of a cliff into the water which is located 4.0 m below. If she is moving at 8.0 m/s the instant she leaves the cliff, determine the following.
Her gravitational potential energy relative to the water surface when she leaves the cliff
Her kinetic energy when she leaves the cliff
Her total mechanical energy relative to the water surface when she leaves the cliff
Her total mechanical energy relative to the water surface just before she enters the water.
The speed at which she enters the water.

Answers

Answer 1

Answer:

1) 2197.44 J

2) 0 J

3) 2197.44 J = Constant

4) 2197.44 J

5) Approximately 8.86 m/s

Explanation:

The given parameters are;

The mass of the diver, m = 56 kg

The height of the cliff, h = 4.0 m

The speed with which the diver is moving, vₓ = 8.0 m/s

The gravitational potential energy = Mass, m × Height of the cliff, h × Acceleration due to gravity, g

1) Her gravitational potential energy = 56 × 4.0 × 9.81 = 2197.44 J

2) The kinetic energy = 1/2·m·u²

Where;

u = Her initial velocity = 0 when she just leaves the cliff

Therefore;

Her kinetic energy when she just leaves the cliff = 1/2 × 56 × 0² = 0 J

3) The total mechanical energy = Kinetic energy + Potential energy

The total mechanical energy is constant

Her total mechanical energy relative to the water surface when she leaves the cliff = Her gravitational potential energy = 2197.44 J = Constant

4) Her total mechanical energy relative to the water surface just before she enters the water = 2197.44 J

5) The speed with which she enters the water, v, is given from, v² = u² + 2·g·h

Where;

u = The initial velocity at the top of the cliff before she jumps= 0 m/s

∴ v² = 0² + 2 × 9.81 × 4 = 78.48

v = √78.48 ≈ 8.86 m/s

The speed with which she enters the water, v ≈ 8.86 m/s

Answer 2

1) Her gravitational potential energy relative to the water surface when she leaves the cliff is; GPE(leaves cliff) = 2195.2 J

2) Her kinetic energy when she leaves the cliff is; KE = 0J

3) Her total mechanical energy relative to the water surface when she leaves the cliff is; ME_total = 2195.2 J

4) Her total mechanical energy relative to the water surface just before she enters the water is; ME_total = 2195.2 J

5) The speed at which she enters the water is; v = 8.85 m/s

We are given;

Mass of the diver; m = 56 kg

Height of the cliff; h = 4 m

Speed at which she is moving; vₓ = 8 m/s

1) Formula for gravitational potential energy is;

GPE = mgh

where;

m is mass

g is acceleration due to gravity

h is height

Thus;

GPE = 56 × 4 × 9.8

GPE(leaves cliff) = 2195.2 J

2) The formula for kinetic energy when she leaves the cliff is;

KE = ¹/₂mu²

Where;

m is mass

u = initial velocity = 0 m/s

Thus;

KE = ¹/₂ × 56 × 0²

KE(leaves cliff) = 0 J

3) The total mechanical energy relative to the water surface when she leaves the cliffis;

ME_total = GPE(leaves cliff) + KE(leaves cliff)

Thus;

ME_total = 2195.2 + 0

ME_total = 2195.2 J  

4) Her total mechanical energy relative to the water surface just before she enters the water is same as that when she leaves the cliff = 2195.2 J

5) The speed with which she enters the water, v, is gotten from newtons third equation of motion;

v² = u² + 2gh

Thus;

v² = 0² + (2 × 9.8 × 4)

v² = 78.4

v = √78.4

v = 8.85 m/s

Read more at; https://brainly.com/question/25708521


Related Questions

What type of substances is an alloy?

A) Moleclue?
B) Mixture?
C) Compound?
D) Element?

Answers

Compound and mixture

a runner makes one lap around a 200m track in 25s, what is the runners (a) average speed and (b) average velocity

Answers

hiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii

Which statement best describes the difference between acceleration and velocity?
A. acceleration only shows a change in direction, but velocity shows a change in speed.

B .acceleration depends on direction, but velocity does not.

C. acceleration is a change in velocity, but velocity is speed in a given direction.

D. acceleration only shows change in speed, but velocity only shows a change in direction.

Answers

c. is the answer because acceleration is the change in velocity in time while velocity is speed with a direction

A 12.0 kg box is being pulled along level ground at constant velocity by a horizontal force of 38.0 N. What is the coefficient of kinetic friction between the box and the floor?

Answers

Coefficient = 0.32
Friction force = 38 = μ x (9.8x12)
μ = 38/117.6 = 0.32

The coefficient of kinetic friction between the box and the floor is 0.323.

By Newton's Law of Motion we understand that an object is at equilibrium if and only if it is at rest or it is moving at constant velocity. If a horizontal force is applied on the box and it is moving, then a force with equal magnitude and opposed to that force must exists, which corresponds to the kinetic friction. Let suppose that the box is moving on a horizontal ground.

The equation of equilibrium for the box is described below:

[tex]\Sigma F = P - \mu_{k}\cdot m\cdot g = 0[/tex] (1)

Where:

[tex]P[/tex] - External force, in newtons.[tex]\mu_{k}[/tex] - Kinetic coefficient of friction, no unit.[tex]m[/tex] - Mass, in kilograms.[tex]g[/tex] - Gravitational constant, in meters per square second.

An expression for the kinetic coefficient of friction is derived by clearing the variable in (1):

[tex]\mu_{k} = \frac{P}{m\cdot g}[/tex] (2)

If we know that [tex]P = 38\,N[/tex], [tex]m = 12\,kg[/tex] and [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], then the kinetic coefficient of friction is:

[tex]\mu_{k} = \frac{38\,N}{(12\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)}[/tex]

[tex]\mu_{k} = 0.323[/tex]

The coefficient of kinetic friction between the box and the floor is 0.323.

We kindly invite to see this question on friction: https://brainly.com/question/18332986

A rally car accelerates from 10 m s−1 to 58 m s−1 in 8 seconds as it moves along a straight road. Given that the acceleration is constant, what is the acceleration of the car?

Answers

Answer:

a = 6 [m/s²]

Explanation:

To solve this problem we must use the following equation of kinematics

[tex]v_{f} =v_{o} +a*t[/tex]

where:

Vf = final velocity = 58 [m/s]

Vo = initial velocity = 10 [m/s]

a = acceleration [m/s²]

t = time = 8 [s]

Now replacing:

58 = 10 + (a*8)

58 - 10 = 8*a

48 = 8*a

a = 6 [m/s²]

Two positively charged particles are 0.03 m apart. The first
particle has a charge of 8.1 C, and the second a charge of 2.6
C. Which change would lead to the smallest increase in the
- electric force between the two particles?
A. Reduce the charge on the first particle by one half.
O B. Double the distance between the particles.
O C. Double the charge on the second particle.
OD. Reduce the distance between the particles by one
half

Answers

The correct option is option C.

Doubling the charge on the second particle produces the smallest increase in force.

Electrostatic force:

Let the given charges be Q and q such that:

Q = 8.1C and q = 2.6C

separated by a distance of R = 0.03m

Now, we have to calculate the minimum increase in electric force.

The electrostatic force is given by:

F  = kQq/R²

Option A is wrong since reducing the charge will reduce the force.

Option B is wrong since the force is inversely proportional to the distance, so increasing the distance will decrease the force.

Option C ⇒ Double the charge on the second particle:

F = 2kQq/R²

Option D ⇒ Reduce the distance between the particles by one half:

So, the new distance between the charges is R/2, then

F = kQq/(R/2)²

F = 4kQq/R²

Clearly, the operation in option C gives the smallest increase in the force.

Learn more about Electrostatic force:

https://brainly.com/question/9774180?referrer=searchResults

When blocking in football, why does a defending lineman often attempt to get his body under that of his opponent and push forward?

Answers

Answer:

because he is trying to break past you and sack your quarterback

Explanation:

With the lineman's weight underneath the defender's, traction is increased with the lineman's feet and the ground. Friction is increased because the total force of both linemen give a larger opposing force of friction, making it harder for the defender to get around him.


What is the Range of the projectile motion?

Answers

Answer:

Range of projectile, R

For projection above ground surface, the range of the angle of projection with respect to horizontal direction, θ, is 0° ≤ θ ≤ 90° and the corresponding range of 2θ is 0° ≤ 2θ ≤ 180°.S

hope you're looking for this.

The range of a projectile is how far it travels in the horizontal direction. If you know the horizontal speed you then multiply by the time in flight and you have the range. I hope this helps :)

Assuming the system is in equilibrium, calculate the missing distance d

Answers

Answer:

d=3.4m

Explanation:

From principle of equilibrium,

TOTAL C.WISE MOMENTS = TOTAL A.C.WISE

10N×d = 2N ×2m + 6N×5m

10Nd =4Nm+ 30Nm

10Nd=34Nm

10N 10N

d=3.4m

The system is in equilibrium, calculate the missing distance d=3.4 m.

What is Displacement?

Displacement is defined as the change in position of an object. It is a vector quantity and has a direction and magnitude.

From principle of equilibrium,

TOTAL C.WISE MOMENTS = TOTAL A.C.WISE

10 N×d = 2 N ×2 m + 6 N×5 m

10 Nd = 4 N m+ 30 N m

10 Nd = 34 N m

d = 3.4 m

The system is in equilibrium, calculate the missing distance d=3.4 m.

To learn more about displacement refer to the link:

brainly.com/question/11934397

#SPJ2

Which does not contain a lens?



a mirror



binoculars



an eye



a camera



Help Me get A good grade PLZ

Answers

Im pretty sure it’s A eye

A race is held between a sports car and a motorcycle. The sports car can accelerate at 5.0 m/s^2 and the motorcycle can accelerate at 8.0 m/s^2. The two vehicles start the race at the same time and accelerate from rest. After 5.0 s, how fast is the sports car going? After 6.0 s, how distance will the motorcycle have gone? To make the race fair, the sports car starts 50.0 m ahead of the motorcycle. If the course is 200.0 m long, which vehicle wins the race?

Answers

Answer:

Vf₁ = 30 m/s

s₂ = 90 m

car wins the race.

Explanation:

To find the speed of car after 5 s, we use 1st equation of motion:

Vf₁ = Vi₁ + a₁t₁

where,

Vf₁ = Final Speed of Car = ?

Vi₁ = Initial Speed of Car = 0 m/s

a₁ = acceleration of car = 5 m/s²

t₁ = time = 5 s

Therefore,

Vf₁ = 0 m/s + (5 m/s²)(5 s)

Vf₁ = 25 m/s

To find the distance of motorcycle after 6 s, we use 2nd equation of motion:

s₂ = Vi₂ t₂ + (1/2)a₂t₂²

where,

s₂ = distance covered by the motorcycle = ?

Vi₁ = Initial Speed of motorcycle = 0 m/s

a₂ = acceleration of motorcycle = 8 m/s²

t₂ = time = 6 s

Therefore,

s₂ = (0 m/s)(6 s) + (1/2)(5 m/s²)(6 s)²

s₂ = 90 m

We can use 2nd equation of motion to find time taken by each car and motorcycle to reach the finish point:

For Car:

s₁ = Vi₁ t₁ + (1/2)a₁t₁²

where,

s₁ = 200 m - 50 m = 150 m (since, car starts 50 m ahead)

Therefore.

150 m = (0 m/s)(t₁) + (1/2)(5 m/s²)t₁²

t₁ = √60 s²

t₁ = 7.74 s

For Motorcycle:

s₂ = Vi₂ t₂ + (1/2)a₂t₂²

where,

s₁ = 200 m

Therefore.

200 m = (0 m/s)(t₂) + (1/2)(5 m/s²)t₂²

t₂ = √80 s²

t₂ = 8.94 s

Since, the car takes less time to reach finish line.

Therefore, car wins the race.

a supersonic aircraft travels faster than the speed of sound. What might be the top speed of such an aircraft? 200 Kilometers per hour 500 Kilometers per hour O 1000 Kilometers per hour O 1500 Kilometers per hour​

Answers

‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎1500 kpm

Which terms describe the motion of most objects in our solar system?
This is a Earth Science question

Answers

Answer:Geography, Earth Science, Astronomy

Rotation describes the circular motion of an object around its center.

Explanation:

Answer:

it is Cyclic and predictable

Why is your physical and mental health important?

Answers

Answer: Mental health and physical health are very closely connected. Mental health plays a major role in your ability to maintain good physical health. Mental illnesses, such as depression and anxiety, affect your ability to participate in healthy behaviors.

Explanation: Hope this helped. Have a great day!!!!

Answer:

Both maths are very important to our daily lives. Physical math helps us understand the reality of life. Learning to do certain math strategies is the first stage to finding answers to problems. Mental math can help us get answers faster through memory. This can help improve strategic methods and strengthen our minds.

Describe Kinetic Energy.​

Answers

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest.

this is also for a Digital Electronics class​

Answers

Answer:

Rt = 908.25 [ohm]

Explanation:

In order to solve this problem, we must remember that the resistors connected in series are added up arithmetically.

In this case, R2 and R3 are in series therefore.

R₂₃ = 200 + 470

R₂₃ = 670 [ohm]

Now this new resistor (R₂₃) is connected in parallel with the resistor R4. therefore we must use the following arithmetic expression, to add resistances in parallel.

[tex]\frac{1}{R_{4-23} }= \frac{1}{R_{4}}+\frac{1}{R_{23} } \\\frac{1}{R_{4-23} }=\frac{1}{1800}+\frac{1}{670} \\R_{4-23}=488.25[ohm][/tex]

In this way R₁, R₅ and R₄₋₂₃ are connected in series.

Rt = R₁ + R₅ + R₄₋₂₃

Rt = 150 + 270 + 488.25

Rt = 908.25 [ohm]


A ferry boat is 4.0 m wide and 6.0 m long. When a truck pulls onto it,
the boat sinks 4.00 cm in the water, What is the weight of the boat?

Answers

Should the question say “what is the weight of the truck”? :)
I can then answer it. There is no information to find the weight of the boat ;)

Erica (39 kg ) and Danny (46 kg ) are bouncing on a trampoline. Just as Erica reaches the high point of her bounce, Danny is moving upward past her at 4.6 m/s . At that instant he grabs hold of her.

Answers

Answer:

V = 2.79 m/s

Explanation:

Momentum before = momentum after

Erica's momentum = 0

Danny momentum = 49 kg * 4.9 m/s = 240.1 kg-m/s

240.1 + 0 = (37 + 49) kg * V

86 V = 240.1

V = 2.79 m/s

What role does the battery play in this circuit design? A) The battery works as the system's wires.
B) The battery is the electrical power supply.
C) The battery is the circuit's main conductor.
D) The battery works as the system's electrical switch.

Answers

Answer:

B

Explanation:

i got it right on the usatestprep

what does this quote mean? ​

Answers

Answer:

Basically, it means that you never know until you try.

Explanation:

A boxer hits punching bag and gives it a change in momentum of 12 kg multiplied by m divided by s over 7.0ms what is the magnitude of the net force on the punching bag

Answers

Answer: 1700

Explanation:

explain the difference in how particles are arranged in a solid,liquids and gases

Answers

Answer:

hope this helps

Explanation:

solid particles are arranged according to the size of the object

while liquid particles are arranged how they move freely together in the object they are in.

while gas particles are arranged scatterly like they spread.

Particles in a: gas are well separated with no regular arrangement. liquid are close together with no regular arrangement. solid are tightly packed, usually in a regular pattern.

my teacher gave us an answer saying "The sugar in soda does this because it doesn’t settle at the bottom of its container." and were supposed to get an 8 letter word and the fourth letter has an s and i dont know what the word is

Answers

Answer:

dissolve

Explanation:

A bus initially moving at 20 m/s with an acceleration of -4m/s² for 5
seconds. What is the displacement AND final velocity?

Answers

Answer:

50m; 0m/s.

Explanation:

Given the following data;

Initial velocity = 20m/s

Acceleration, a = - 4m/s²

Time, t = 5secs

To find the displacement, we would use the second equation of motion;

[tex] S = ut + \frac {1}{2}at^{2}[/tex]

Substituting into the equation, we have;

[tex] S =20*5 + \frac{1}{2}*(-4)*5^{2}[/tex]

[tex] S =100 + (-2)*25[/tex]

[tex] S =100 - 50[/tex]

S = 50m

Next, to find the final velocity, we would use the third equation of motion;

[tex] V^{2} = U^{2} + 2aS [/tex]

Where;

V represents the final velocity measured in meter per seconds. U represents the initial velocity measured in meter per seconds. a represents acceleration measured in meters per seconds square.

Substituting into the equation, we have;

[tex] V^{2} = 20^{2} + 2(-4)*50 [/tex]

[tex] V^{2} = 400 - 400[/tex]

[tex] V^{2} = 0[/tex]

V = 0m/s

Therefore, the displacement of the bus is 50m and its final velocity is 0m/s.

what is the slope of the line

Answers

Answer:

[tex]m=\frac{1}{3}[/tex]

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Algebra I

Slope Formula: [tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

Explanation:

Step 1: Define

Point (0, -1)

Point (3, 0)

Step 2: Find slope m

Substitute:                    [tex]m=\frac{0+1}{3-0}[/tex]Add/Subtract:               [tex]m=\frac{1}{3}[/tex]

what is biosphere hydrosphere and atmosphere

Answers

Answer:

Biosphere are the regions of the surface, atmosphere, and hydrosphere of the earth.

Hydrosphere is when all the waters on the earth's surface, such as lakes and seas, and sometimes including water over the earth's surface, such as clouds.

Atmosphere is the envelope of gases surrounding the earth or another planet.

Explanation:

Hope this helps you out !!!

Compare the momentum of a 7160 kg truck moving at 5.00 m/s to the
momentum of a 2240 kg car moving at 15.0 m/s.

Answers

Answer:

2,200

Explanation:

truck=35800,car=33600

Which is one limitation to technological design?

being innovative
designing a solution
having product appeal
identifying a problem

Answers

Answer:

c. Having product appeal

Explanation:

Answer:

c

Explanation:

What type of motion is illustrated in the diagram below?


A. Oscillating motion faster than the speed of sound.
B. Oscillating motion slower than the speed of sound.
C. Circular motion faster than the speed of sound.
D. Circular motion slower than the speed of sound.

Answers

Answer:

Explanation:

C

PLS HELP WILL GIVE 50 POINTS
How is energy sent from Earth to space?
conduction and convection
radiation and conduction
reflection and conduction
radiation and reflection

Answers

Answer:

I'm pretty sure its radiation and reflection. Some of the Sun's energy gets reflected off into space. (I could be wrong though)

Answer:

radiation and reflection

hope helps you

have a nice day

Explanation:

hope this will surely be helpful to you

Other Questions
Solve the following formula for b 4a - b=c Page1/1Compltez les phrases avec : sur, sous, entre, dans, gauche, devant, derrire 2pViviane est ...sa chambre, sur son lit. Son chien, Kiki, est..la table. Mousse, son chat,est..la porte. Son petit ballon en peluche estle vase fleurs. Ltagre estletableau et laffiche. Le tableau est.., laffiche est droite.2. Traduisez en roumain 3pa) Dans la salle de classe il y a vingt-huit lves.b) On ma remis une lettre pour vous.c) Elles font la cuisine..d) Quand quelquun veut, il peut..3. Compltez votre carte didentit 3pNomPrenom:NationalitVille:Pays:+ 2 p Un mes Rodrigo alquil 2 pelculas y 3 juegos de video con un costo total de $230.50. El prximo mes l alquil 4 pelculas y 8 juegos de video con un costo total de $580.00. Hallar el costo de alquiler de cada pelcula y de cada juego de video. Which element for WICKED was used for the first time in the London version of the musical and the creative team liked it so much that they put it into the set design for the NEW YORK Broadwayshow? A group of 17 men and 24 women are attending an awards banquet. Each banquet table can seat 8 people.What is the least number of tables needed for the banquet? Help, Will mark brainliest and 5 STARS who does bruno write a letter to at the end of chapter 8 Sara has $75 to spend on clothes. She wants to buy a pair of jeans that cost $27 and spendthe rest on t-shirts. Each t-shirt costs $8. How many t-shirts can Sara afford to buy? Which of the following statements best describes the profits tenant farmers would receive in a sharecroppingsystem?A. Tenant farmers kept all othe profits from harvested crops.B. Tenant farmers kept most profits from crops sold and also kept supplies, free of charge.C. Tenant farmers kept some profits from crops sold, minus expenses and supply costs.D. Tenant farmers received none of the profits from selling crops.Plzz hirry Give reasons for why it is isosceles After our sun leaves the main sequence it will most likely...A.) become a supergiant and explode in a supernova explosionB.) become a giant and eventually form a black holeC.) become a supergiant and eventually form a dwarf starD.) become a giant and eventually form a dwarf star What is Isaac Newtons third law of motion? Explain? pls help me tbis is being timed Use the drop-down menus to complete statements that describe SmartArt categories.Information that does not need to be shown sequentially can be displayed as a_A _shows a continuous process.The way various elements in a system interconnect can be shown as a_A _ displays different elements according to importance or size.i did this because we don't have a lot of answers for computer classes I know the answers no need to answer The Consumer Financial Protection Bureau protects the interests of customers by ensuring that federal consumer-protection laws are enforced. True or False? Fill in the blank with the French word that best completes the following sentence.To see what time it is, you can look atla clochela pendulel'horairele compashurry please PLEASE READ THIS ITS ATACTHMENT TO PART 1Part 2Buck : Dazed, suffering intolerable pain from throat and tongue, with the life half throttled out of him, Buck attempted to face his tormentors.But he was thrown down and choked repeatedly, till they succeeded in filing the heavy brass collar from off his neck. Then the rope was removed, and he was flung into a cagelike crate. here he lay for the remainder of the weary night, nursing his wrath and wounded pride. Buck: And each time the joyful bark that trembled in Bucks throat was twisted into a savage growl. But the saloon-keeper let him alone and he could not understand what it all meant. What did they want with him, these strange men? Why were they keeping him pent up in this narrow crate? He did not know why, but he felt oppressed by the vague sense of impending calamity and in the morning four men entered and picked up the crate. Whereupon he lay down sullenly and allowed the crate to be lifted into a wagon. Then he, and the crate in which he was imprisoned, began a passage through many hands. Clerks in the express office took charge of him; he was carted about in another wagon; a truck carried him, with an assortment of boxes and parcels, upon a ferry steamer; he was trucked off the steamer into a great railway depot, and finally he was deposited in an express car. For two days and nights this express car was dragged along at the tail of shrieking locomotives; and for two days and nights Buck neither ate nor drank. In his anger he had met the first advances of the express messengers with growls, and they had retaliated by teasing him. He flung himself against the bars, quivering and frothing. He did not mind the hunger so much, but the lack of water caused him severe suffering and fanned his wrath to fever pitch. Buck:That had given them an unfair advantage; but now that it was off, he would show them. They would never get another rope around his neck. His eyes turned bloodshot, and he was metamorphosed into a raging fiend. Four men gingerly carried the crate from the wagon into a small, high-walled backyard. A stout man, with a red sweater that sagged generously at the neck, came out and signed the book for the driver. That was the man, Buck divined, the next tormentor, and he hurled himself savagely against the bars. The man smiled grimly, and brought a hatchet and a club.Driver: You aint going to take him out now? What is the atomic mass (mass number) of this atom?ab,c090408O1O PLS HURRY!!!! 15 PTS!!! The pictures represent three different states of matter.Which order of pictures places molecules with the mostamount of motion to the least amount of motion?O X Y ZO ZYXO Y ZO Y - X - Z In the news clip, why must then-supreme court nominee Brett Kavanaugh appear before the senate judiciary committee to answer questions? To eliminate the y-terms and solve for x in the fewest steps, by which constants should the equations be multiplied by before adding the equationstogether?First Equation: 5x - 4y = 28Second equation: 3x - 9y = 30The first equation should be multiplied by 3 and the second equation by 5.The first equation should be multiplied by 9 and the second equation by -4.The first equation should be multiplied by 3 and the second equation by -5.The first equation should be multiplied by 9 and the second equation by 5.