The time it takes for a rocket to hit the ground is 3 seconds
Step-by-step explanation:
We are given equation for height as
where
x is the time in seconds
When object hits the ground
then height becomes 0
so, we can set h(x)=0
and then we can solve for x
Subtract both sides by 18
So,
the time it takes for a rocket to hit the ground is 3 seconds