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If 2x + y = -8 and -4x + 2y = -16, what is the value of y?

User Ekalavya
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1 Answer

3 votes

Answer:

y = -8

Explanation:

Solve as a system of equations

2x + y = -8 multiply this equation by 2

-4x + 2y = -16 Do not change

Solving: 4x + 2y = -16

-4x +2y = -16

4y = -32

y = -8

2x + y = -8 Solve for x

2x = -y - 8

x = -y/2 - 8/2

x = -1/2y - 4 Substitute this into your second equation

-4x + 2y = -16

-4(-1/2y - 4) + 2y = -16

2y -16 +2y = -16

4y - 16 = -16

4y = -32

y = -8 x = -1/2(-8) -4 = 4 - 4 = 0

Checking the answer

2(0) + -8 = -8

-4(0) +2(-8) = -1 6 = 0 -16 = -16

User Chan
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