<PRE><B>Question 491531</B>
Megan factored the expression 28x^2+x-15 as (4x-3)(7x+5). But when Jacob applied the FOIL principle and multiplied out (4x-3)(7x+5), he got 28x^2-x-15; thus, Megan’s solution does not appear to check. Why is that? 
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Megan did not factor correctly.
28x^2+x-15 
28x^2 +21 -20x - 15
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7x(4x+3) -5(4x+3)
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(4x+3)(7x-5)
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Cheers,
Stan H.
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