Advanced Math practice question

Answer: -6

The axis satisfies −b/2 = 3, so b = −6.

Common wrong answers

If you answered 3

3 is the axis itself; b is −2 · 3 = −6.

If you answered 6

x = −b/(2a) = 3 with a = 1 forces b to be negative: b = −6.

If you answered -3

Multiply by 2: b = −2 · 3 = −6.

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