physics
posted by reese .
A ball thrown horizontally at 17.0 m/s from the roof of a building lands 36.3 m from the base of the building.
How tall is the building?
could someone PLEASE tell me how to go about solving this problem!

The distance of 36.3 m from the building and the horizontal velocity tells you how long the ball was in the air.
This calculated time, together with the acceleration due to gravity should enable you to calculate the drop in height of the ball. 
The time taken to travel the horizontal distance of 36.3m derives from t = 36.3/17 = 2.135 sec.
The height of the building then derives from
h = Vo(t) + gt^2/2 or
h = 0(2.135) + 4.9(2.135)^2 or
h = 22.33m.