SOLUTION: how do I solve 7x+y=10 2x+3y=-8

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Question 61414: how do I solve 7x+y=10
2x+3y=-8
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
7X+Y=10
2X+3Y=-8 YOU HAVE TO ELIMINATE ONE OF THE VARIABLES THUS: MULTIPLY THE FIRST EQUATION BY -3 AND THEN ADD THESE TWO EQUATIONS THUS
-21X-3Y=-30
2X+3Y=-8
--------------------------------
-19X=-38
X=-38/-19
X=2 NOW SUBSTITUTE 2 FOR X IN EITHER EQUATION & SOLVE FOR Y
7*2+Y=10
14+Y=10
Y=10-14
Y=-4
PROOF
2*2+3*-4=-8
4-12=-8
-8=-8