Question

Help please,
The height in feet, h, reached by a projectile after t seconds is given by the function:

h(t) = -16t2 + 110t + 5

a)During what time interval did the projectile reach an altitude of at least 135 ft?Write your answer using interval notation. Round to 2 decimal places.

b) When will it hit the ground?Round to 2 decimal places.

Answer 1

a).
put h(t) = 135 ft
135 = -16t^2 + 110t + 5
now slove the quadratic

b). Put h(t) = 0

Answer 2

thank you, I got it.

Answer 3

anytime :)