Answer:
2s or 3s
Step-by-step explanation:
Given the function that models the height of the object as;
h(t) = - 16t^2 + 80t + 96
The ball reaches the ground when h = 0
Substitute
0 = - 16t^2 + 80t + 96
Divide through by -16
0 = t²-5t-6
t²-5t-6 = 0
t²-2t-3t+6 = 0
t(t-2)-3(t-2) = 0
(tt-2)(t-3) = 0
t - 2 = 0 and t-3 = 0
t = 2 and 3s
Hence it will take the ball 2s or 3s to reach the ground
