SOLUTION: Hello I was wondering if you would be able to assist me please, as I am stuck on some problems which I have no idea how to start. An example is as follows and I am asked to factor

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Hello I was wondering if you would be able to assist me please, as I am stuck on some problems which I have no idea how to start. An example is as follows and I am asked to factor      Log On


   

Question 126876: Hello I was wondering if you would be able to assist me please, as I am stuck on some problems which I have no idea how to start. An example is as follows and
I am asked to factorize the following 27X^3 + 8Y^3
Any help would be greatly appreciated. Cheers D.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

27x%5E3%2B8y%5E3 Start with the given expression.


%283x%29%5E3%2B%282y%29%5E3 Rewrite 27x%5E3 as %283x%29%5E3. Rewrite 8y%5E3 as %282y%29%5E3.


%283x%2B2y%29%28%283x%29%5E2-%283x%29%282y%29%2B%282y%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


%283x%2B2y%29%289x%5E2-6xy%2B4y%5E2%29 Multiply and simplify

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Answer:

So 27x%5E3%2B8y%5E3 factors to %283x%2B2y%29%289x%5E2-6xy%2B4y%5E2%29.

In other words, 27x%5E3%2B8y%5E3=%283x%2B2y%29%289x%5E2-6xy%2B4y%5E2%29