SOLUTION: if A does a work in x hrs n b in x+6hrs then how much time will it require if both work together?? please give explanation of the solution

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Question 291994: if A does a work in x hrs n b in x+6hrs then how much time will it require if both work together??
please give explanation of the solution
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
if A does a work in x hrs, and b in x+6 hrs, then how much time will it require if both work together??
:
let t = time required when they work together
let the completed job = 1
:
A shared work equation
t%2Fx + t%2F%28%28x%2B6%29%29 = 1
multiply equation by x(x+6), results:
t(x+6) + xt = x(x+6)
tx + 6t + xt = x^2 + 6x
2tx + 6t = x^2 + 6x
factor out t
t(2x+6) = x^2 + 6x
divide both sides by (2x+6)
t = %28x%5E2%2B6x%29%2F%282x%2B6%29 is the time when they work together (in terms of x)
;
Each one will do a fraction of the work, the two fractions add up to 1 which is the completed job