7 + 3 = 10 those are the 2 addens
Answer:
6
Step-by-step explanation:
Answer:
0.64 seconds.
Step-by-step explanation:
When it hits the ground h(t) = 0.
0 = -16t^2 + 4t + 4
-4(4t^2 - t -1) = 0
t = [-(-1) +/- sqrt (1 - 4*4*-1)] / 8)
t = 0.64, -0.39
answer is 0.64 seconds.