Question 478497
4s-5t=18
6s+10t=-8 

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Multiply thru the 1st equation by 2:
8s-10t = 36
6s+10t = -8
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Add and solve for "s":
14s = 28
s = 2
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Solve for "t" using any of the equations:
4s-5t = 18
4*2-5t = 18
-5t = 10
t = -2
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Cheers,
Stan H.
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