SOLUTION: I need to factor this out by trial-and-error....
(D) 40x^2+7x-20
Can you plz explain step by step so I understand what your doing...thnx.
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-> SOLUTION: I need to factor this out by trial-and-error....
(D) 40x^2+7x-20
Can you plz explain step by step so I understand what your doing...thnx.
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Question 439399: I need to factor this out by trial-and-error....
(D) 40x^2+7x-20
Can you plz explain step by step so I understand what your doing...thnx. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 40x^2+7x-20
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Use Inverse FOIL:
Find two numbers whose
product is 40*-20 = -800
and whose sum is +7
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The numbers are 32 and -25
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= 40x^2 +32x-25x -20
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= 8x(5x+4) -5(5x+4)
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Factor:
= (5x+4)(8x-5)
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Cheers,
Stan H.
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