SOLUTION: if 12x+13y=29 and 13x+12y=21,then find x-y

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Question 1105648: if 12x+13y=29 and 13x+12y=21,then find x-y
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!

Any clever way to get to x-y ?

13x%2B12y-%2812x%2B13y%29=21-29
13x-12x%2B12y-13y=-8
highlight%28x-y=-8%29----------yes, this way




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This would not be necessary:
12x%2B13x%2B13y%2B12y=29%2B21
25x%2B25y=50
x%2By=2