SOLUTION: When you do the substitution method and you just have variables to add and subtract with..Like for example. x+y=3 x-y=1 How do you solve that?

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Question 620526: When you do the substitution method and you just have variables to add and subtract with..Like for example.
x+y=3
x-y=1
How do you solve that?
Found 2 solutions by vleith, ewatrrr:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
x%2By=3
x-y=1
Use the first equation and put it in a format that shows one variable in terms of the other. Lets take equation one and change it to show x in terms of y
x%2By=3
x+=+3-y
Now that the second equation and substitute in the value you just found for x
x-y=1
%283-y%29+-+y+=+1
Now simplify and solve for the remaining variable
-2y+=+1-3
-2y+=+-2
y+=+1
Take this value for y and use it in the first equation and solve for x
x+%2B+1+=+3
x+=+2
So the solution is (2,1)

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Elimination Method works well for this ex:

x+y=3

x-y=1

2x = 4

 x = 2   and   y = 1   (as x + y = 3)

 ordered pair (2,1) the solution for this System of Equations