SOLUTION: solve the linear system -7x-8y=9 -4x+9y=-22

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Question 280032: solve the linear system
-7x-8y=9
-4x+9y=-22

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
-7x-8y=9 multiply by 9
-4x+9y=-22 multiply by 8 & add.
-63x-72y=81
-32x+72y=-176
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-95x=-95
x=-95/-95
x=1 ans.
-7*1-8y=9
-7-8y=9
-8y=9+7
-8y=16
y=16/-8
y=-2 ans.
SOLUTION: (1,-2)
-7x-8y=9
-8y=7x+9
y=7x/-8+9/-8
y=-7x/8-9/8 (red line)
-4x+9y=-22
9y=4x-22
y=4x/9-22/9 (green line)
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-7x%2F8+-9%2F8+%2C+4x%2F9+-22%2F9+%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -7x/8 -9/8 and 4x/9 -22/9).