Question

The height of a soccer ball that is kicked from the ground can be approximated by the function:

y = -12x^2 + 48x

where y is the height of the soccer ball in feet x seconds after it is kicked. What is the soccer ball's maximum height in feet?​

Answer 1

Answer: 4 seconds

Explanation:

x refers to time. Since we want to know how long it is in the air, we need to find the time (x) when the ball lands on the ground (y = 0)

0 = -12x² + 48x

0 = -12x(x - 4)

0 = -12x 0 = x - 4

0 = x 4 = x

x = 0 seconds is when the ball was kicked

x = 4 seconds is when the ball landed on the ground