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Solve the system using the substitution technique:(−3, 1)(−3, 11)(3, 11)(−3, −1)

Solve the system using the substitution technique:(−3, 1)(−3, 11)(3, 11)(−3, −1)-example-1
User KPD
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1 Answer

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Answer:

The solution to the system of equations is (-3, 1)

Step-by-step explanation:

The given system of equations is:

4x + 2y = -10............(1)

3x + 9y = 0..............(2)

Divide equation (1) through by 2

2x + y = -5

Make y the subject of the formula

y = -5 - 2x.........(3)

Substitute equation (3) into equation (2)

3x + 9(-5 - 2x) = 0

3x - 45 - 18x = 0

18x - 3x = -45

15x = -45

x = -45/15

x = -3

Substitute x = 3 into equation (3)

y = -5 - 2(-3)

y = -5 + 6

y = 1

Therefore, the solution to the system of equations is (-3, 1)