SOLUTION: Please demonstrate how to solve the following equations by the substitution method: y=x+3 2x+y=15

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Question 208863: Please demonstrate how to solve the following equations by the substitution method:
y=x+3
2x+y=15
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Please demonstrate how to solve the following equations by the substitution method:
y=x+3
2x+y=15
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Since y is already isolated in the 1st eqn, sub for y into the 2nd eqn.
2x + y = 15
2x + (x+3) = 15
3x + 3 = 15
3x = 12
x = 4
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y = x+3
y = 7