SOLUTION: please help me solve these equations. 9a+18=5.17c 4.97a+46.93=5.17c

Algebra ->  Systems-of-equations -> SOLUTION: please help me solve these equations. 9a+18=5.17c 4.97a+46.93=5.17c      Log On


   



Question 356647: please help me solve these equations.
9a+18=5.17c
4.97a+46.93=5.17c

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
9a+18=5.17c
4.97a+46.93=5.17c
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Rearrange:
9a - 5.17c = -18
4.97a-5.17c = =-46.93
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Subtract the bottom equation from the top and solve for "a":
4.03a = 28.93
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a = 7.1787
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Substitute into 9a-5.17c = -18 to solve for "c":
9(7.1787)-5.17c = -18
-5.17c = -82.6079
c = 15.9783..
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Cheers,
Stan H.