Question

A bird drops a stick to the ground from a height of 90 ft. The function h=16ft^2+90 gives the sticks approximate height h above the ground, in feet, after t seconds. At about what time does the stick hit the ground? How many seconds does it hit the ground?

Answer 1

The stick hits the ground 2.37 seconds after it is dropped.

Explanation:

Your function is incorrect.

I will assume that the correct function is

h = -16t² + 90

When the stick hits the ground, its height is 0.

We are looking for the value of t, time, when h = 0.

Set h = 0, and solve for t.

h = -16t² + 90

-16t² + 90 = 0

-16t² = -90

t² = 5.625

t = 2.37

The stick hits the ground 2.37 seconds after it is dropped.