Answer:
2.16 s
Step-by-step explanation:
When it hits the ground, height h=0 hence
0=45-10t-5t^{2}
5t^{2}+10t-45=0
t^{2}+2t-9=0
Using quadratic formula
x=-1+\sqrt 10\\ x=-1-\sqrt 10
Since time can't be negative, -1+\sqrt 10
t=2.16 s
Answer:
Step-by-step explanation:
i need help to
Answer:
answer choice 2
Step-by-step explanation:
Answer:
D) 5.52
Step-by-step explanation:

Step-by-step explanation:
