Question

Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth.

A rocket is launched from atop a 101-foot cliff with an initial velocity of 116 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.

Answer 1

8.0 seconds to the nearest tenth,

Explanation:

h=-16t^2 +vt + c.

-16t^2 + 116t + 101 = 0

t = [ -116 + /- √(116^2 - 4*-16*101) ] / (-32)

t = (-116 +/- √19920) / (-32)

t = -0.79, 8.036 (we ignore the negative root)

The time in flight = 8.036 seconds.