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Aleonysh [2.5K]

3 years ago

13

SUPER URGENT!!!!!!!!!!!!!NEED ANSWERED NOW!!!! PLS!!!

1 answer:

Oxana [17]3 years ago

7 0

The solution of the system of equations is (-3 , -2)

Step-by-step explanation:

Let us revise the steps of Linear combinations method

Arrange the equations with like terms in columns
make the coefficients of x or y equal in magnitudes and different in signs
Add the equations and solve for the remaining variable
Substitute the value of the variable into one of the two equations to find the second variable

The system of equations is

3 x - 8 y = 7 ⇒ (1)

x + 2 y = -7 ⇒ (2)

Let us make the coefficients of y equal in magnitude by multiplying

equation (2) by 4

∴ 4 x + 8 y = -28 ⇒ (3)

- Add equations (1) and (3) to solve for x

∴ 7 x = -21

- Divide both sides by 7

∴ x = -3

Substitute the value of x in equation (1) to find y

∵ 3(-3) - 8 y = 7

∴ -9 - 8 y = 7

- Add 9 to both sides

∴ -8 y = 16

- Divide both sides by -8

∴ y = -2

The solution of the system of equations is (-3 , -2)

Learn more:

You can learn more about the system of the linear equations in brainly.com/question/2115716

#LearnwithBrainly

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