SOLUTION: How is this question done? x8 -1296y4

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Question 725420: How is this question done?
x8 -1296y4
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
To start, x%5E8-1296y%5E4 can be factored as a difference of squares.
x%5E8=%28x%5E4%29%5E2 and 1296y%5E4=%2836y%5E2%29%5E2
You must have been told that
a%5E2-b%5E2=%28a-b%29%28a%2Bb%29 where a and b can be any expression, so
x%5E8-1296y%5E4=%28x%5E4%2B36y%5E2%29%28x%5E4-36y%5E2%29

x%5E4%2B36y%5E2 cannot be factored using just real numbers,
but x%5E4-36y%5E2 is a difference of squares, so
x%5E4-36y%5E2=%28x%5E2%2B6y%29%28x%5E2-6y%29

For an answer, you should just write: