Advanced Math practice question

Answer: 7

Factor: (x − 3)(x − 4) = 0, so x = 3 or x = 4. Their sum is 7. (For x² + bx + c = 0 the roots always sum to −b.)

Common wrong answers

If you answered 1

1 is 4 − 3, the difference of the roots.

If you answered 12

12 is the PRODUCT of the roots (3 × 4), which equals the constant term.

If you answered -7

−7 is b itself; the sum of the roots is −b = 7.

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