A firecracker shoots up from a hill 145 feet high, with an initial speed of 80 feet per second. Using the formula H(t) = -16t2 + vt + s, approximately how long will it take the firecracker to hit the ground?

Question

anonymous · Answer

@IMStuck @mathstudent55

anonymous · Answer

Do you know what each variable stands for? ie s t v

anonymous · Answer

yes the equation is h(t)=-16t^2+80t+145

anonymous · Answer

By what I can tell you just need to plug in the values into the quadratic formula and solve for t in place of x

anonymous · Answer

i tried that

anonymous · Answer

wasn't one of the answers

anonymous · Answer

What are the answers?

anonymous · Answer

13 11 9 and 6

anonymous · Answer

Okay gimme a minute, I'll try to solve it

anonymous · Answer

thank you

anonymous · Answer

Out of curiosity what were your answers when you plugged it in

anonymous · Answer

nvm

anonymous · Answer

Well I think i have the answer I just wanted to see what you got

anonymous · Answer

When I plug it in I get t=6.4 seconds