SOLUTION: Solve by the elimination method: 7r-9s=-35 9r+7s=85

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Question 333423: Solve by the elimination method:
7r-9s=-35
9r+7s=85
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
7r-9s=-35
9r+7s=85
..
multiply first equation by -9 and equation2 by 7
-63r+81s=315
63r+49s=595
81s+49s=595+315
130s=910
s= 7
..
plug value of s in first equation
7r-9s=-35
7r-63=-35
7x=28
x= 4