Answer:
Step-by-step explanation:
Your equation is weird. The position equation for this situation is
[tex]s(t)=-4.9t^2+15t+7[/tex] and set it equal to 0 to solve for the time it takes to hit the ground. Those times come out to be
t = 3.47 sec and t = -.411 sec. But since time can never be negative, our time is 3.47 seconds
(What is that -52?)