SOLUTION: Need help solving this equation. {{{4/r=(5r-5)/(r^2-3r)}}}

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Question 851996: Need help solving this equation.
4%2Fr=%285r-5%29%2F%28r%5E2-3r%29
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
That starts as a rational equation; but through simplification, it will quickly become a quadratic equation. Simplest common denominator is r%28r%5E2-3r%29. Multiply left and right members by this and you will see, ... and should know what to do.

You should find r%5E2-7r=0 on your way to the full solution.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Need help solving this equation.
4%2Fr=%285r-5%29%2F%28r%5E2-3r%29


4%2Fr+=+%285r+-+5%29%2F%28r%5E2+-+3r%29_______r%3C%3E+0   AND    r+%3C%3E+3

r%285r+-+5%29+=+4%28r%5E2+-+3r%29 ------- Cross-multiplying

5r%5E2+-+5r+=+4r%5E2+-+12r

5r%5E2+-+4r%5E2+-+5r+%2B+12r+=+0

r%5E2+%2B+7r+=+0

r%28r+%2B+7%29+=+0

r = 0 (ignore)       OR      r + 7 = 0____highlight_green%28r+=+-+7%29