Question

A firecracker shoots up from a hill 150 feet high with an initial speed of 110 feet per second. Using the formula H(t) = -16t2 + vt + s, approximately how long will it take the firecracker to hit the ground?

8 seconds
9 seconds
10 seconds
11 seconds

Answer 1

well what do you know about the height of a object when it hits the ground

Answer 2

?

Answer 3

the heavier it is the faster it hits the ground but i dont understand the equation

Answer 4

what math class are you in

Answer 5

algebra 1

Answer 6

you know that when the ball hits the ground the height is 0, however you have some missing parts of your equation


using the initial values they give you

the height at t=0 is 150 [h(0)=150]

and plugging into the equation you should get s

Answer 7

so 9 seconds

Answer 8

9?