SOLUTION: Divide. 2x-6/21 divide 5x-15/12

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Question 97946: Divide.
2x-6/21 divide 5x-15/12
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%28%282x-6%29%2F21%29%2F%28%285x-15%29%2F12%29 Start with the given expression


%28%282x-6%29%2F21%29%2A%2812%2F%285x-15%29%29 Multiply by the reciprocal of the second fraction



%282%28x-3%29%2F21%29%2A%2812%2F%285x-15%29%29 Factor out 2 out of 2x-6


%282%28x-3%29%2F21%29%2A%2812%2F5%28x-3%29%29 Factor out 5 out of 5x-15


%282%2Across%28x-3%29%2F21%29%2A%2812%2F%285%2Across%28x-3%29%29%29 Cancel out like terms


%282%2F21%29%2A%2812%2F5%29 Simplify


24%2F105 Multiply the two fractions


8%2F35 Simplify

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
[(2x-6)/21] / [(5x-15)/12]

Invert and multiply:
[(2x-6)/21] * [12/(5x-15)]
Cancel the 3 factor common to numerator and denominator to get:
[(2x-6)/7] * [4/(5x-15)]
Factor to get:
[2(x-3)/7] * [4/(5(x-3)]
Cancel the (x-3) factor common to numerator and denominator to get:
[2/7]
= 8/35
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cheers,
Stan H.