When it hits the ground, then h=0
find the xintercept or in this case the tintercepts
c=76
v=135
h=-16t^2+135t+76
use quadratic formula
ax^2+bx+c=0
x=

a=-16
b=135
c=76
x=

x=

x=

aprox
x=-0.5297 or 8.967
exclude the negative root since you can't have negative time
means that it takes 8.97 seconds to hit the ground
Answer:
3240
Step-by-step explanation:
6/0.5*9*10=270*12=3240
I think its carrot by = 8x7