Question

A firecracker shoots up from a hill 150 feet high with an initial speed of 95 feet per second. Using the formula H(t) = −16t2 + vt + s, determine how long it will take the firecracker to hit the ground.

6.5 seconds

7.9 seconds

7.2 seconds

7.6 seconds

Answer 1

H(t) = −16t2 + vt + s
H(t)=0 cuzz ground is at zero
s=150 cuzz that is the intial height we shoot it from that one hill.
v=95 initial velocity
t is just variable so we leave it as t now we plug in.

Answer 2

0 = −16t2 + (95)t + (150)

now we solve. Thru factoring, graphing, completing square or quadratic formula.

quad formula is best i think

7.233545019
7.2

Answer 3

my crappy graphical representation drawing :P dont laugh