<PRE><B>Question 439399</B>
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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