SOLUTION: how do you solve-9x+16y=9 5x+8y=-5 using elimination?

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Question 572979: how do you solve-9x+16y=9 5x+8y=-5 using elimination?

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
-9x+16y= 9
5x+ 8y=-5
.
to get rid of the y's, we multiply both sides of the bottom equation by -2:
-9x+16y= 9
-10x-16y=10
--------------
-19x =19
x = -1
.
substitute the above into:
5x+ 8y=-5
5(1)+ 8y=-5
5+ 8y=-5
8y=-10
y= -10/8
y= -5/4
.
solution: (-1, -5/4)