I need help for this math problem

Question

You throw a basketball from a height of 5 feet with an upward velocity of 20 feet per second. The function  gives the height  of the basketball after  seconds. When does the basketball hit the floor? Round your answer to the nearest tenth.

Answer 1

The correct function is

h(t) = -16t² + 20t + 5

with h(t) in feet and t in seconds. To find when it reaches the floor, set h(t)=0 and solve for t using the quadratic formula. You will get a positive and a negative solution. Since time starts at t=0, the positive solution is correct.