SOLUTION: How would this be solve 8x^3-27y^3

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Question 687172: How would this be solve 8x^3-27y^3
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

8x%5E3-27y%5E3 Start with the given expression.


%282x%29%5E3-%283y%29%5E3 Rewrite 8x%5E3 as %282x%29%5E3. Rewrite 27y%5E3 as %283y%29%5E3.


%282x-3y%29%28%282x%29%5E2%2B%282x%29%283y%29%2B%283y%29%5E2%29 Now factor by using the difference of cubes formula. Remember the difference of cubes formula is A%5E3-B%5E3=%28A-B%29%28A%5E2%2BAB%2BB%5E2%29


%282x-3y%29%284x%5E2%2B6xy%2B9y%5E2%29 Multiply

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Answer:

So 8x%5E3-27y%5E3 factors to %282x-3y%29%284x%5E2%2B6xy%2B9y%5E2%29.

In other words, 8x%5E3-27y%5E3=%282x-3y%29%284x%5E2%2B6xy%2B9y%5E2%29