Question

PLEASE HELP ME I ONLY HAVE 20 MINUTES!!!!

Answer 1

$h(x) = 40x - 16x^2\\h(x) = 15\\40x - 16x^2 = 15\\-16x^2 + 40x - 15 = 0$

Using the quadratic formula we get

$x_1 = 0.5\\x_2 = 2.04$

Therefore the tennis ball is at least 15 feet above the ground from 0.5 seconds to 2.04 seconds