SOLUTION: Solve by the addition method 7x-4y=-3 x+2y=5 #24 x-y=3 -6x+6y=17

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Solve by the addition method 7x-4y=-3 x+2y=5 #24 x-y=3 -6x+6y=17      Log On


   

Question 72860This question is from textbook Intermediate Algebra
: Solve by the addition method
7x-4y=-3
x+2y=5


#24
x-y=3
-6x+6y=17 This question is from textbook Intermediate Algebra

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
7X-4Y=-3 NOW MULTIPLY THE SECOND EQUATION BY -7 & ADD
-7X-14Y=-35
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-18Y=-38
Y=-38/-18
Y=38/18
Y=19/9 SOLUTION, NOW SUBSTITUTE (19/9) FOR Y & SOLVE FOR X
X+2*19/9=5
X+38/9=5
X=5-38/9
X=(45-38)/9
X=7/9 ANSWER.
PROOF
7*7/9-4*19/9=-3
49/9-76/9=-3
(49-76)/9=-3
-27/9=-3
-3=-3