Answer:
43.75feet
Step-by-step explanation:
Given the height of the tennis ball expressed as;
h(t) = -15t^2 + 45t + 10
At maximum height, the velocity of the ball is zero
v = dh/dt
dh/dt = -30t + 45
Since dh/dt = 0, hence;
0 = -30t + 45
30t = 45
t = 45/30
t = 3/2
t = 1.5secs
Substitute t = 1.5 into the expression given
h(1.5) = -15(1.5)^2 + 45(1.5) + 10
h(1.5) = -15(2.25)+67.5+10
h(1.5) = -33.75+77.5
h(1.5) = 43.75feet
Hence the maximum height of the ball is 43.75feet
