SOLUTION: please help Use substitution to solve for x and y 4x + y = -5 2x - y = -1

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Question 61695This question is from textbook Alegbra Concepts and Applications
: please help
Use substitution to solve for x and y
4x + y = -5
2x - y = -1 This question is from textbook Alegbra Concepts and Applications

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
4X+Y=-5 OR Y=-4X-5 NOW SUBSTITUTE (-4X-5) FOR Y IN THE SECOND EQUATION
2X-(-4X-5)=-1
2X+4X+5=-1
6X=-1-5
6X=-6
X=-6/6
X=-1 SOLUTION NOW SOLVE FOR Y
4*-1+Y=-5
-4+Y=-5
Y=-5+4
Y=-1 SOLUTION
PROOF
2*-1-(-1)=-1
-2+1=-1
-1=-1