SOLUTION: x=y-4 3x+y=12 solve the linear system using substitution

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Question 727145: x=y-4
3x+y=12
solve the linear system using substitution
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

x=y-4....eq.1
3x%2By=12....eq.2
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to solve the linear system using substitution, substitute value of x from eq.1 in eq.2
3%28y-4%29%2By=12....eq.2..solve for y
3y-12%2By=12
3y%2By=12%2B12
4y=24
y=24%2F4
highlight%28y=6%29
go back to eq.1 and find x
x=y-4....eq.1...plug in y=6

x=6-4
highlight%28x=2%29