SOLUTION: I need help factoring this polynomial. Thanks 9x^2 + 4 y^2= .

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Question 192455: I need help factoring this polynomial. Thanks
9x^2 + 4 y^2= .
Found 2 solutions by Alan3354, Earlsdon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I need help factoring this polynomial. Thanks
9x^2 + 4 y^2= .
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It's a sum of 2 squares, it's not factorable (without imagianary numbers).

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor:
9x%5E2%2B4y%5E2 This is not factorable into rational factors.
The only way that you can factor this is with irrational factors:
9x%5E2%2B4y%5E2+=+%283x-2yi%29%283x%2B2yi%29 where i+=+sqrt%28-1%29
To see this, multiply the two factors given above using the FOIL method:
%283x-2yi%29%283x%2B2yi%29+=+9x%5E2%2B6xyi-6xyi-4y%5E2i%5E2
But i%5E2+=+-1 so make this substitution...
9x%5E2%2B6xyi-6xyi-4y%5E2i%5E2+=+9x%5E2%2B4y%5E2