SOLUTION: Solve by substitution 3x -y =-7 and x+ y = -9

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Question 87524: Solve by substitution 3x -y =-7 and x+ y = -9
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
3X-Y=-7
-Y=-3X-7
Y=3X+7 NOW SIBSTITUTE (3X+7) FOR X IN THE OTHER EQUATION
X+(3X+7)=-9
X+3X+7=-9
4X=-9-7
4X=-16
X=-16/4
X=-4 ANSWER.
3*-4-Y=-7
-12-Y=-7
-Y=-7+12
-Y=5
Y=-5 ANSWER.