SOLUTION: how do you use the substitution method for the problem x+y=4 y=3x

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Question 546456: how do you use the substitution method for the problem x+y=4
y=3x
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=4
y=3x

substitute y in first equation
x+3x=4
4x=4
/4
x=1
so y=3
because x+y=4