SOLUTION: A canoe takes 4/t hours to travel upstream and (10-t)/(t plus2) hours to travel downstream, What expression represents the total time it takes the canoe to travel both ways? Th

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: A canoe takes 4/t hours to travel upstream and (10-t)/(t plus2) hours to travel downstream, What expression represents the total time it takes the canoe to travel both ways? Th      Log On


   



Question 444887: A canoe takes 4/t hours to travel upstream and (10-t)/(t plus2) hours to travel downstream,
What expression represents the total time it takes the canoe to travel both ways?
The answer key says (3T plus 18)/ ( t squared plus 2t).
Don't see how this is the answeR. I added the fractions together.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A canoe takes 4/t hours to travel upstream and (10-t)/(t plus2) hours to travel downstream,
What expression represents the total time it takes the canoe to travel both ways?
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(4/t)+(10-t)/(t+2)
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least common denominator: t+2
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= [(t+2)(4/t)+(10-t]/(t+2)
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=[4+(8/t)+10-t]/(t+2)
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= [4t + 8 + 10t-t^2]/(t(t+2))
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= [-t^2+14t+8]/(t^2+2t)
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= [-(t^2-14t-8)]/(t^2+2t)
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Cheers,
Stan H.
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The answer key says (3T plus 18)/ ( t squared plus 2t).