SOLUTION: solve by substitution x + 3y = 2 -x + y = 1

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: solve by substitution x + 3y = 2 -x + y = 1      Log On


   

Question 206601: solve by substitution
x + 3y = 2
-x + y = 1
Answer by Marth(57) About Me  (Show Source):
You can put this solution on YOUR website!
You can choose to eliminate either x or y by substitution; x is easier. Put the second equation in the form x=
-x%2By=1
x=y-1


Now replace x in the first equation with y-1
x%2B3y=2
y-1%2B3y=2
4y-1=2
4y=3
y=3%2F4


Use that value of y in one of the equations to find x.
-x%2B3%2F4=1
-x=1%2F4
x=-1%2F4