posted by Anonymous .
a projectile is launched straight up with an initial velocity of 112 feet per second. how long would it take to reach 180 feet?
d = Vo*t + 0.5g*t^2 = 180,
112t - 16t^2 - 180 = 0,
Divide both sides by 4:
28t - 4t^2 - 45 = 0,
-4t^2 + 28t - 45 = 0.
X = 2.5s. Use Quadratic Formula and use
the smaller of the 2 solutions.