Question 333423
7r-9s=-35
9r+7s=85
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multiply first equation by -9 and equation2 by 7
-63r+81s=315
63r+49s=595
81s+49s=595+315
130s=910
s= 7
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plug value of s in first equation
7r-9s=-35
7r-63=-35
7x=28
x= 4