SOLUTION: Solve by the elimination method: 5r-8s=-26 8r+5s=83

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Question 392526: Solve by the elimination method:
5r-8s=-26
8r+5s=83
Found 2 solutions by stanbon, NancyLam:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Solve by the elimination method:
5r-8s=-26
8r+5s=83
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Multiply thru 1st equation by 8.
Multiply thru 2nd equation by 5.
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40r-64s = -8*26
40r+25s = 5*83
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Subtract the top equation from the bottome and solve for "s":
89s = 623
s = 7
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Solve for "r":
5r-8*7 = -26
5r = -26 + 56
5r = 30
r = 6
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Cheers,
Stan H.

Answer by NancyLam(35) (Show Source):
You can put this solution on YOUR website!
5r-8s=-26 (mitiply 5)= 25r-40s=-130(Write equation)
8r+5s=83 (mutiply 8)= 64r+40s= 664(Write equation)

25r-40s=-130(rewrite equation)
64r+40s= 664(Write equation)
89r+0s = 534(add 2 equation)
r= 534/89 (solve for y)
r=6
subtitution r=6 for find y
5(6)-8s=-26
30 -8s =-26
s = -26-30/-8
s = 7