SOLUTION: solve systemes of equation by following the substitution method 5x-2y=18 2x-y=7

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Question 135049: solve systemes of equation by following the substitution method

5x-2y=18 2x-y=7
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
2x-y=7 or -y=-2x+7 or y=2x-7 now substitute (2x-7) for y in the other equation.
5x-2(2x-7)=18
5x-4x+14=18
x=18-14
x=4 answer.
y=2*4-7
y=8-7
y=1 answer.
proof:
5*4-2*1=18
20-2=18
18=18