Advanced MathHardTime to reach a maximum from vertex form
Advanced Math practice question
The height h, in metres, of a kite above the ground t minutes after it is launched is modelled by h(t) = −(t − 6)² + 20 for the first few minutes. After how many minutes does the kite reach its greatest height?
Answer: 6
The vertex form shows the maximum, 20, at t = 6.
Common wrong answers
- If you answered 3
- 3 halves 6.
- If you answered 20
- 20 is the greatest height, not the time.
- If you answered -6
- −6 misreads the sign in (t − 6).
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