SOLUTION: Solve each system by the substitution method. x+3y=2, -x+y=1

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Question 360831: Solve each system by the substitution method. x+3y=2, -x+y=1
Found 2 solutions by ewatrrr, Jstrasner:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi, 

x+3y=2, -x+y=1

Solving by the substitution method

-x+y=1

y - 1 = x

(y-1)+3y=2

solving for y

4y - 1 = 2

4y = 3

y = 3/4

x = y - 1

x = (-1/4)

checking our answer

-(-1/4) + 3/4 = 1

1/4 + 3/4 = 1

Answer by Jstrasner(112) About Me  (Show Source):
You can put this solution on YOUR website!
Hey,
for this one we need to isolate one of the variables and substitute what it equals with it in the other equation:
-x+y=1 => y=x+1
Then in the next equation:
x+3y=2 => x+3(x+1)=2 then: x+3x+3=2 => 4x=-1 => x= -(1/4)
Then we substitute x for -(1/4) into the other equation: y=x+1 => y= -(1/4) +1 =>
y= (3/4)
Therefore:
x= -(1/4)
y= (3/4)
I hope this works!