High school maths

Question

A baseball is thrown in the air at a velocity of 60 feet per second. Using the formula         h(t)=60t-16t^2 how long does it take for the ball to hit the ground?

Answer 1

h(t) = 60t - 16t² = 4t (15 - 4t)

 

h = 0 ⇒ 15 - 4t = 0 ⇒ t = 15/4 s = 3.75s

 

t = 3.75s