SOLUTION: solve using the substitution method {{{8s + 12t = 16 }}} {{{6s + 9t = 12}}} I could really use some help on this one please.

Algebra ->  Expressions-with-variables -> SOLUTION: solve using the substitution method {{{8s + 12t = 16 }}} {{{6s + 9t = 12}}} I could really use some help on this one please.      Log On


   

Question 333493: solve using the substitution method
8s+%2B+12t+=+16+
6s+%2B+9t+=+12

I could really use some help on this one please.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
solve using the substitution method
8s + 12t = 16
6s + 9t = 12
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Reduce the equations
8s + 12t = 16 --> 2s + 3t = 4
6s + 9t = 12 --> 2s + 3t = 4
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It's the same equation --> no unique solution.
They're dependent --> infinite # of solutions.
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8s + 12t = 16
6s + 9t = 12 --> s = (4-3t)/2
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Sub for s in the 1st eqn
8(4-3t)/2 + 12t = 16
16 - 12t + 12t = 16
16 = 16