Question

The height (metres) of an object is given by h(t) = -2t² + 9t + 56 where t is time is seconds. When does the object hit the ground?

Answer: 8 seconds

Answer 1

8 seconds

Explanation:

-2t^2+9t+56=0

-2t^2+16t-7t+56=0

-2t(t-8)-7(t-8)=0

(-2t-7)(t-8)=0

-2t-7=0 or t-8=0

t-8=0

t=8