Question

PLEASE HELP ME PLS ITS MATH

Answer 1

9

Explanation:

We know that

`h(t)=-16t^2+1296`

The balls hits the ground when h(t)=0, so

`-16t^2 + 1296=0 \\ \\ t^2 - 81=0 \\ \\ t^2 = 81 \\ \\ t=9`

Note I only considered the positive case because time must be positive.