You can put this solution on YOUR website! Factor: 80X^2-40x-75
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Divide by 5
= 5(16x^2 - 8x - 15)
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16 has 3 pairs of factors
1*16
2*8
4*4
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15 has 2 pairs
1*15
3*5
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Find the combination that gives -8x
The factors of 15 have different signs.
Also, since 8 is an even number, the outside and inside products have to be both even, since they can't both be odd.