Question

A boy throws a baseball across a field. The ball reaches its maximum height, 18 meters, after 1 second. After approximately 2.3 seconds, the ball lands on the ground. The ball’s motion can be modeled using the function f(x) = –10x2 + 20x + 8. What is the height of the ball 1.5 seconds after it is thrown?

Answer 1

Answer: 15.5

Explanation:

Answer 2

Since the ball will reach the maximum height of 18 meters after 1 second, meaning after 1 second it will start to go down. So will expect that the height will be lower than 18 m after 1.5 s.

f(x) = –10x2 + 20x + 8
f(x) = –10(1.5^2) + 20(1.5) + 8
f(x) = 15.5 m