SOLUTION: 8x + 8y = -16 8x + 9y = -8 solve using elimination

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Question 793867: 8x + 8y = -16
8x + 9y = -8
solve using elimination
Answer by waynest(281) About Me  (Show Source):
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8x + 8y = -16
-(8x + 9y = -8)
= -y = -8
y = 8
solve for x in the first equation
8x + 8(8) = -16
8x + 64 = -16
8x + 64 - 64 = -16 - 64
8x = -80
8x/8 = -80/8
x = -10
check:
8(-10) + 8(8) = -16
-80 + 64 = -16
-16 = -16
8(-10) + 9(8) = -8
-80 + 72 = -8
-8 = -8