By defining that h(t) = 0 means that the ball is in the ground, we conclude that the ball is thrown at t = 0, and hits the ground again at t = 2.
The height equation is:
h(t) = -14*t^2 + 28*t
When t = 0, we have: h(0) = 0
So it is in the ground, meaning that it is thrown at the time t = 0.
We need to find the other root of the quadratic equation, so we need to solve:
-14*t^2 + 28*t = 0
We can rewrite this as:
t*(-14*t + 28) = 0
The parenthesis is zero when:
-14*t + 28 = 0
t = 28/14 = 2
So at t = 2, the ball hits the ground.
If you want to learn more about quadratic equations, you can read:
https://brainly.com/question/1214333
