The height h (in feet) of a piece of candy, t seconds after being thrown, is given by
h = −16t2 + 16t + 32.
After how many seconds will the candy hit the ground?
You want to know the time when the height is equal to zero, so just plug in 0 for h and solve for t.
0 = -16t2 + 16t + 32
reduce everything by -16
0 = t2 - t - 2
you can use the quadratic equation or you can factor it.
0 = (t-2)(t+1)
set each factor equal to 0
t=2 and t=-1
since time can't be negative, you know it is t=2
2 seconds
