Advanced Math practice question

Answer: 1/2 or 0.5

Factor: (2x + 5)(x − 3) = 0, so x = 3 or x = −5/2. Sum: 1/2. (Or −b/a = 1/2 directly.)

Common wrong answers

If you answered 1

1 uses −b without dividing by a = 2.

If you answered 3

3 is one root alone.

If you answered -1/2

−1/2 has the wrong sign; the sum of roots is −b/a = −(−1)/2.

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