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A diver is standing on a platform 24 feet above the pool. He dives form the platform with an initial upward velocity of 8 feet per

second is dive is modeled by the equation h = -16- + 8t + 24, where h is his height above the water att seconds. How long will
it take the diver to hit the water?
A)
1 second
0:05:21
B)
15 seconds
2 seconds
2.5 seconds

User Eli Nathan
by
3.8k points

1 Answer

1 vote

Answer:

It should be t = 1.5 seconds if your equation is h(t) = -16*t^2 + 8t + 24

Explanation:

h(t) = -16*t^2 + 8t + 24

We want to solve for t when h(t) = 0.

This is a parabolic equation so basically we can use the quadratic formula to solve this.

h(t) = -16*t^2 + 8t + 24

0 = h(t) = -16*t^2 + 8t + 24

take out the 8

0 = -2t^2 + t + 3

0 = -2t*t - 2t + 3t + 3

0 = -2t * (t + 1) + 3*( t + 1)

0 = (-2t + 3) * ( t + 1)

so time cannot be negative, so we choose 0 = (-2t + 3), t = 3/2 seconds

or t = 1.5 seconds

User Josh Bond
by
4.4k points