SOLUTION: System of Equations by Substitution Solve each system by substitution. 7x+y=0 2x-y=9

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Question 347108: System of Equations by Substitution

Solve each system by substitution.
7x+y=0
2x-y=9
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.7x%2By=0
2.2x-y=9
.
.
.
From eq. 2,
y=2x-9
Substitute into eq. 1,
7x%2B%282x-9%29=0
9x-9=0
9x=9
highlight%28x=1%29