SOLUTION: 5/x + 7/6 = 4/(x-4), solve for x. I am confused as to how I come up with the LCD for these to be able to solve for x

Algebra ->  Expressions-with-variables -> SOLUTION: 5/x + 7/6 = 4/(x-4), solve for x. I am confused as to how I come up with the LCD for these to be able to solve for x      Log On


   



Question 172127: 5/x + 7/6 = 4/(x-4), solve for x.
I am confused as to how I come up with the LCD for these to be able to solve for x

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
5/x + 7/6 = 4/(x-4)
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Since you have an equation you don't want an lcd, you want a least common
multiple.
lcm = 6x(x-4)
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Multiply thru by the lcm to get:
5*6(x-4) + 7x(x-4) = 4*6x
30x-120 + 7x^2-28 = 24x
7x^2 + 6x - 148 = 0
Solve with the quadratic formula
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Cheers,
Stan H.