SOLUTION: How do you solve by the addition-or-subtraction method? 2x+y=18 2x-y=22

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Question 173664: How do you solve by the addition-or-subtraction method?
2x+y=18
2x-y=22
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
this is simply another name for process of elimination meaning your eliminating one of the variables...this equation is perfectly set up to eliminate the y terms because +y-y=0...we are left with 2x+2x=18+22
:
4x=40
:
highlight%28x=10%29
:
now take x's value and plug it back into either equation I will use the first equation
:
2(10)+y=18
:
highlight%28y=-2%29
:
sure enough a graph shows intersection at (10,-2)
graph%28300%2C300%2C-15%2C15%2C-15%2C15%2C-2x%2B18%2C2x-22%29