Question 1060727
substitution method. 
-5x-8y=17
2x-7y=-17
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2x-7y=-17 --> x = (7/2)y - 17/2
Sub for x in the 1st eqn.
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-5x-8y=17
-5*((7/2)y - 17/2) - 8y = 17
Multiply by 2 to eliminate fractions.
-5*(7y - 17) - 16y = 34
-35y + 85 - 16y = 34
-51y = -51
y = 1
====
x = (7/2)y - 17/2
x = -5
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That's the hard way.
-5x-8y=17 times -2 --> 10x+16y = -34
2x-7y=-17 --> 2x = 7y-17 times 5 --> 10x = 35y-85
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sub for 10x
35y-85 + 16y = -34
51y = 51
etc