PLEASE HELP!!!!!! MEDAL TO RIGHT ANSWER! Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth.
A rocket is launched from atop a 76-foot cliff with an initial velocity of 135 ft/s.
A.) Substitute the values into the vertical motion formula h=-16t^2+vt+c. Let h=0
B.) Use the quadratic formula find out how long the rocket will take to hit the ground after it is launched. Round to the nearest tenth of a second.
1.)0= -16t^2 + 135t + 76; 0.5 s
2.)0= -16t^2 + 135t + 76; 9 s
3.)0= -16t^2 + 76t + 135; 9 s
4.)0= -16t^2 + 76t + 135; 0.5 s

Question

PLEASE HELP!!!!!! MEDAL TO RIGHT ANSWER! Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth.
A rocket is launched from atop a 76-foot cliff with an initial velocity of 135 ft/s. 
A.) Substitute the values into the vertical motion formula h=-16t^2+vt+c. Let h=0
B.) Use the quadratic formula find out how long the rocket will take to hit the ground after it is launched. Round to the nearest tenth of a second.
1.)0= -16t^2 + 135t + 76; 0.5 s
2.)0= -16t^2 + 135t + 76; 9 s
3.)0= -16t^2 + 76t + 135; 9 s
4.)0= -16t^2 + 76t + 135; 0.5 s

anonymous · Answer

Can i get some help? maby...:(

mertsj · Answer

ok.  hang on.  had to deal with another problem.

mertsj · Answer

Well, we can eliminate 3 and 4 right away because the original velocity is wrong.  Do you agree?

anonymous · Answer

Yep!

anonymous · Answer

I would have to say it is #2, what do you think?

oaktree · Answer

To solve this just plug in the answer to b into a and see if you get 0. Whichever one works is the correct answer.

anonymous · Answer

Still not sure can you write it out please?

mertsj · Answer

$$x=\frac{-135\pm \sqrt{135^2-4(-16)(76)}}{-32}$$

mertsj · Answer

$$x=\frac{-135\pm \sqrt{23089}}{-32}=\frac{-135\pm152}{-32}=9$$