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Hurry. A catapult launches a pumpkin with an upward velocity of 150 ft./s.

The height of the pumpkin, h, in feet after t seconds is given by the
function h = -16t2 + 150t + 20. How long does it take the
pumpkin to reach its maximum height? What is the pumpkin's
maximum height? Round to the nearest hundredth, if necessary.

User SEGV
by
4.1k points

1 Answer

3 votes

Answer:

Time taken to reach maximum height=4.69 seconds

Maximum Height=371.56feet

Explanation:

Given the height function of the pumpkin:

[Tex]h = -16t^2 + 150t + 20[/tex]

The pumpkin reaches it's maximum height at its axis of symmetry.

Therefore, we determine its equation of symmetry.

The equation of symmetry:

[Tex]t=-\frac{b}{2a}[/tex]

a=-16, b=150.

Therefore:

[Tex]t=-\frac{150}{2*-16}=4.6875[/tex]

The pumpkin reaches maximum height after 4.6875 seconds.

At t=4.6875

[Tex]h = -16(4.6875)^2 + 150(4.6875)+ 20\\=371.5625\approx 371.56 \:feet[/tex]

The pumpkin's maximum height is 371.56 feet.

User Japzdivino
by
4.7k points