Question 408890
h(t)=-16t^2+42t+3.5
set h(t) to zero and solve for t:
0=-16t^2+42t+3.5
apply the quadratic formula to give us:
t = {-0.08, 2.71}
we can throw out the negative solution leaving us with:
t = 2.71 seconds
.
details of quadratic formula follows:
*[invoke quadratic "x", -16, 42, 3.5 ] = 0