Question

The function Y equals -16 X squared plus velocity X models the height of a football in feet X seconds after a player kicks it. In the equation of the function, velocity is the balls initial velocity in feet per second. The ball hits the ground two seconds after the player kicks it. What is the value of velocity?

Answer 1

Explanation:

If we are looking for v, the equation is

`y=-16x^2+vt`, assuming that the ball was on the ground before it was kicked. If it takes 2 seconds to hit the ground after being kicked, we replace y with 0 since the height of something on the ground has no height at all. We also replace x with 2, since it takes 2 seconds for the ball to be at the height of 0:

`0=-16(2)^2+v(2)` and

0 = -64 + 2v and

-2v = -64 so

v = 32 feet per second