SOLUTION: A ball is thrown upward with an initial velocity of 343 m/sec. When will it be 4900 meters high? I have been trying to help my son with his Algebra. I am having such a hard time

Question 724396: A ball is thrown upward with an initial velocity of 343 m/sec. When will it be 4900 meters high? I have been trying to help my son with his Algebra. I am having such a hard time. Could some one please show and explain to me an eqation to figure this problem out?
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
A ball is thrown upward with an initial velocity of 343 m/sec. When will it be 4900 meters high?
-------------------
The equation for ht vs. time should be given with the problem.
If not, the commonly used is
h(t) = -4.9t^2 + vt + C, t in seconds, h & C in meters
--------
h(t) = -4.9t^2 + 343t = 4900
4.9t^2 - 343t + 4900 = 0
t^2 - 70t + 1000 = 0
(t - 20)*(t - 50) = 0
t = 20 seconds going up
t = 50 seconds falling
=======================
That's a good throw, ~ 767 mi/hr

RELATED QUESTIONS
A tennis ball is thrown vertically upward with an initial velocity of +6.9 m/s. What... (answered by richard1234)

A ball is thrown upward with an initial speed of 24.5 m/s. When is it 19.6m high? (answered by Alan3354)

When a basketball player shoots a ball from his hand at an initial of 2 m with an initial (answered by Alan3354)

A ball is thrown directly upward from ground level with an initial speed of 80ft/s. How... (answered by mathstutor494)

A tennis ball is thrown vertically upward with an initial velocity of +8.0cm/s. a.What... (answered by Alan3354)

A tennis ball is thrown vertically upward with an initial velocity of +7.4 m/s. What... (answered by Alan3354)

A ball is thrown upward from the roof of a building 100 m tall with an initial velocity... (answered by Nate)

A ball is thrown upward from the roof of a building 100 m tall with an initial velocity... (answered by Edwin McCravy)

A ball is thrown vertically upward from the ground with an initial velocity of... (answered by ikleyn)