SOLUTION: I need to know how to solve x+y=4 and y=3x using the substitution method.

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Question 301702: I need to know how to solve x+y=4 and y=3x using the substitution method.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%2By=4
2.y=3x
Substitute eq. 2 into eq. 1 for y and solve for x.
Then go back and use either equation (eq. 2 is quickest) to solve for y.