Respuesta :
Answer:
3 seconds
Step-by-step explanation:
The given equation describes a parabolic curve with zeros at x=-1 and x=7. The line of symmetry of the curve is halfway between the zeros, at ...
x = (-1 +7)/2 = 6/2 = 3
The maximum of the curve is on the line of symmetry. The ball will reach its maximum height 3 seconds after being thrown.
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Additional comment
The maximum height will be 16 meters.

Answer:
12 meters
Step-by-step explanation:
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