SOLUTION: I am working on Factoring Polynomial completely - I think I figured this one out, but would appreciate someone looking over to let me know if I did this correctly. 4m (exponent

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Question 21454: I am working on Factoring Polynomial completely - I think I figured this one out, but would appreciate someone looking over to let me know if I did this correctly.
4m (exponent of 2) - 9m - 9
my solution: 2(2m*(3) 2(2m*(3) Is this correct? Thank you very much for your help.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Ummm...let's see, if we multiply your factors together, we should get the original expression, right?
%282%282m%2A%283%29%29%282%282m%2A%283%29%29%29%29+=+%282%286m%29%29%282%286m%29%29 = %2812m%29%2812m%29+=+144m%5E2
We didn't get the original expression, so your factors don't work!
Here's how it should go.
Factor:
4m%5E2+-+9m+-+9
Your factors will have the form of: (am + 3)(bm - 3), why? because:
(-3)(3) = -9 This will get the constant term in the equation.
Now you need (a)(b) to = 4 and you need (a)(-3)+(b)(3) = -9, the x-coefficient.
Try:
a = 4 and b = 1: (4)(1) = 4 and (4)(-3)+(1)(3) = -12+3 = -9 So this works.
The factors are:
4m%5E2+-+9m+-+9+=+%284m+%2B+3%29%28m+-+3%29
Check:
Multiply the factors using FOIL.
%284m+%2B+3%29%28m+-+3%29+=+4m%5E2+-+12m+%2B+3m+-+9 = 4m%5E2+-+9m+-+9