Question 213996: Please help me solve the substituation x+y=12 and x-y=-4. I can't figure out how to solve these Found 2 solutions by Alan3354, drj:Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website! There's more than one method. The easiest method for this pair is elimination and substitution.
x+y=12
x-y=-4
--------- Add the 2 equations
2x = 8
x = 4
------
Sub for x into either eqn
x+y = 12
4+y = 12
y = 8
----- Answer by drj(1380) (Show Source): You can put this solution on YOUR website! Please help me solve the substitution x+y=12 and x-y=-4. I can't figure out how to solve these.
The following will solve the system of linear equations by substitution.
Solve: We'll use substitution. After moving 1*y to the right, we get: , or . Substitute that
into another equation: and simplify: So, we know that y=4. Since , x=8.
Answer: .
I hope the above steps were helpful.
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