SOLUTION: Factor completely: 8z^3+125

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Question 316985: Factor completely:
8z^3+125
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

8z%5E3%2B125 Start with the given expression.


%282z%29%5E3%2B%285%29%5E3 Rewrite 8z%5E3 as %282z%29%5E3. Rewrite 125 as %285%29%5E3.


%282z%2B5%29%28%282z%29%5E2-%282z%29%285%29%2B%285%29%5E2%29 Now factor by using the sum of cubes formula. Remember the sum of cubes formula is A%5E3%2BB%5E3=%28A%2BB%29%28A%5E2-AB%2BB%5E2%29


%282z%2B5%29%284z%5E2-10z%2B25%29 Multiply

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Answer:

So 8z%5E3%2B125 factors to %282z%2B5%29%284z%5E2-10z%2B25%29.

In other words, 8z%5E3%2B125=%282z%2B5%29%284z%5E2-10z%2B25%29