SOLUTION: I need help solving these sentences 9x+8y=14 -4x+y=12

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Question 289138: I need help solving these sentences

9x+8y=14
-4x+y=12
Found 2 solutions by jim_thompson5910, brucewill:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
If we multiply both sides of -4x%2By=12 by -8 we then get 32x-8y=-96. Now add this equation to the first equation to get: %289x%2B8y%29%2B%2832x-8y%29=14-96. Combine like terms to get: 41x=-82. Finally, solve for 'x' by dividing both sides by 41 to get x=-2. Now use this answer to solve for 'y'. I'll let you do that.


Answer by brucewill(101) About Me  (Show Source):
You can put this solution on YOUR website!
9x + 8y = 14
-4x + y = 12
First, we need to make one variable subtractable (or addable) from the other. In this case, I choose y. Multiple the second equation by 8:
9x + 8y = 14
-32x + 8y = 96
Now, subtract the second equation from the first:
41x = -82
highlight%28x+=+-2%29
Substitute the x = -2 into the first equation:
9(-2) + 8y = 14
-18 + 8y = 14
8y = 32
highlight%28y+=+4%29
Prove the answer, substituting into the original equations:
-18 + 32 = 14. OK.
8 + 4 = 12. OK.