SOLUTION: Factor the polynomial. x^2 - 3x - 40

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Question 144995: Factor the polynomial.
x^2 - 3x - 40
Found 2 solutions by stanbon, shahid:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Factor the polynomial.
x^2 - 3x - 40
Using the AC method:
= x^2-8x+5x-40
= x(x-8) +5(x-8)
=(x-8)(x+5)
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Cheers,
Stan H.

Answer by shahid(44) About Me  (Show Source):
You can put this solution on YOUR website!
find prime factors of 40 i-e 2,2,2,5 now form two factors whose difference is coefficient of middle term which is -3 this is called middle term breacking
x^2-8x+5x-40 -8+5=-3 and 8 x 5 = 40 so we r at right path
x(x-8)+5(x-8) taking pairwise common
(x-8)(x+5) required factors