Question

HELP ME PLEASEEEEE!!!!!!!!!!!!!
If a football player passes a football from 4 feet off the ground with an initial velocity of 36 feet per second, how long will it take the football to hit the ground? Use the equation h = -16t2 + 36t + 4.

quantity of 9 plus or minus square root of 65 all over 8

9 plus or minus square root of 65 end root over 8

quantity of 9 plus or minus square root of 97 all over 8

9 plus or minus square root of 97 end root over 8

Answer 1

so when it hits the ground, what will the height be? 0 right?

Answer 2

um yea

Answer 3

so
0=-16*t^2 +36*t +4

Answer 4

divide both sides by 4

Answer 5

which gives you
0=-4*t^2 + 9*t +1

Answer 6

then you use the quadratic equation to solve for t

Answer 7

I have problem when it comes to this part I don't understand it

Answer 8

ok

Answer 9

what is tripping you up

Answer 10

when I do it the answer is never one of the choices

Answer 11

well all of the answers are in the form of the quadratic equation, so you really dont have to solve the quadratic

Answer 12

for this case, a = -4, b = 9, c = 1

Answer 13

or you can divide by -1, and get

a=4, b=-9, c=-1

Answer 14

which will give you

9 plus or minus the square root of 65 all over 8

Answer 15

which is one of your answers