Question 1093601
I think the formula needed is
-16t^2+19.5t+6.5=f(x)
It passes through 10 feet on its way up and down.
Therefore, set it equal to 10 and when 10 is subtracted from both sides
-16t^2+19.5t-3.5=0
t=-1/32{-19.5+/- sqrt (380.25-224)}; sqrt term is sqrt(156.25)=12.5
t=(-1/32)(-7)=7/32 seconds This is when the ball was on its way to the basket.  
t=(-1/32){-19.5-12.5}=1 second
{{{graph(300,300,-1,3,-10,20,-16x^2+19.5x+6.5,10)}}}
How long would the ball fly?  
-16t^2+19.5t+6.5=0.  Here, we want the time when h(t)=0.
t=-(1/32)(-19.5+/- sqrt(19.5^2+416); sqrt term=28.22)
t=-(1/32)(47.72)=1.49 sec.