SOLUTION: 2r-75=-5 7r+2s=9 solve with elimination method

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Question 228576: 2r-75=-5
7r+2s=9
solve with elimination method
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
2r-75=-5
2R=-5+75
2R=70
R=70/2
R=35 ANS.
7r+2s=9
7*35+2S=9
245+2S=9
2S=9-245
2S=-236
S=-236/2
S=-118 ANS.
PROOF:
7*35+2*-118=9
245-236=9
9=9