SOLUTION: How can I factor this by grouping 5x^3-20x^2+9x-36

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Question 777975: How can I factor this by grouping
5x^3-20x^2+9x-36
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

5x%5E3-20x%5E2%2B9x-36 Start with the given expression


%285x%5E3-20x%5E2%29%2B%289x-36%29 Group the terms in two pairs


5x%5E2%28x-4%29%2B9%28x-4%29 Factor out the GCF 5x%5E2 out of the first group. Factor out the GCF 9 out of the second group


%285x%5E2%2B9%29%28x-4%29 Since we have the common term x-4, we can combine like terms


So 5x%5E3-20x%5E2%2B9x-36 factors to %285x%5E2%2B9%29%28x-4%29


In other words, 5x%5E3-20x%5E2%2B9x-36=%285x%5E2%2B9%29%28x-4%29