home work
posted by Steven .
The ball is throw in to the air . If its height in feet is given by  16t^2 + 64t, at what time t will the ball reach a height of 64 feet?

just solve
 16t^2 + 64t = 64
Let's get rid of that pesky factor of 16, leaving
t^2  4t + 4 = 0
(t2)^2 = 0
t = 2