SOLUTION: How do you solve x+y=13, x-y=15 by substitution.

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Question 955207: How do you solve x+y=13, x-y=15 by substitution.
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

x%2By=13....eq.1
x-y=15....eq.2
-------------------------- by substitution
x%2By=13....eq.1...solve for x
x=13-y....substitute in eq.2

13-y-y=15....eq.2...solve for y
13-2y=15
13-15=2y
-2=2y
y=-1
go to x=13-y substitute -1 for y, and solve for x
x=13-%28-1%29
x=13%2B1
x=14