A ball is thrown from a height of 217 feet with an initial downward velocity of 17 ft/s
h=217-17t-16t^2
Round your answer to the nearest hundreds. Please HELP!

Question

A ball is thrown from a height of 217 feet with an initial downward velocity of 17 ft/s
h=217-17t-16t^2
Round your answer to the nearest hundreds. Please HELP! <3

anonymous · Answer

are you solving for time?

anonymous · Answer

yes it is how long it takes for the ball to hit the ground

anonymous · Answer

I think you may have wrote your equation wrong: 
If I'm not mistaken, the kinematic for horizontal freefall is this:
Hf-Hi=Vi-1/2gt^2

anonymous · Answer

$$H_f-H_i=V_i-\frac{ 1 }{ 2 }g*t^2$$

anonymous · Answer

Thank you so much for helping me. I think I did write it wrong. This little sign I used "^" was reffering to a squared root. The equation to use is t=-b + (square root) b^(exponent 2)-4ac/2x5

anonymous · Answer

oops I mean ^ as an exponent of 2

anonymous · Answer

now, just plug into the quadratic and you're are done.

anonymous · Answer

ive done it so many times and can not figure out the right answer :/ I know you just plug all of it in and then you should get the answer but it keeps coming up as wrong

anonymous · Answer

$$0=217-17t-16t^2 \rightarrow x= 3.19s$$

anonymous · Answer

wow you are amazing

anonymous · Answer

er it should have been t=3.19s but you know what I mean. All I did was plug into a quadratic solver.

anonymous · Answer

Just have to be careful with how you write the equation out and you'll be fine. good luck.

anonymous · Answer

Thankyou what is the quadratic solver?

anonymous · Answer

just google quadratic solver and you will get sites that allow you to plug in the values of a,b, and c and it will spit out your answers.

anonymous · Answer

I cant even find out how to get to that point to type it in..

anonymous · Answer

what point?