A stone is thrown from the top of a building upward at an angle of 30.0 to the horizontal and with an initial speed of 25.0m/s ,if the heights of the building is 75.0m..How long is the flight?

Answer 1

hf=hi+vi*t-4.9t^2
0=75+25*t-4.9t^2

solve this quadratic equaation with the qudratic formula....