Advanced Math practice question

Answer: -7

The product expands to 6x² − 7x − 20; subtracting 6x² leaves −7x − 20, so b = −7.

Common wrong answers

If you answered 7

The cross terms give 8x − 15x = −7x; the sign is negative.

If you answered -11

The cross terms are 2x · 4 = 8x and −5 · 3x = −15x, totaling −7x.

If you answered -20

−20 is c, the constant; b is the x-coefficient −7.

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