Advanced Math practice question

Answer: -13 or −13

Zeros at −2 and 5 mean f(x) = (x + 2)(x − 5) = x² − 3x − 10. So b = −3, c = −10, and b + c = −13.

Common wrong answers

If you answered 3

3 is the SUM of the zeros. b is the negative of that sum, and the question asks for b + c.

If you answered 13

13 has the right size but the wrong sign; both b and c are negative here.

If you answered -7

−7 comes from b = 3 and c = −10 — the sign of b is wrong. (x + 2)(x − 5) has middle term −5x + 2x = −3x.

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