Check for Understanding Problem Earlier, you were told about a toy rocket fired into the air from the top of a barn. Its height (h) above the ground in yards after a seconds is given by the function: h(x) = -5x2 + 10x + 20 What was the maximum height of the rocket? Solution The maximum height was reached by the rocket at one second as you found in part b from the previous example. It takes 1second to reach the maximum height. We will substitute that value in for x in our function and simplify. The maximum height reached by the rocket was 25 yards. What is the time it takes fo the rocket to hit the ground? (Use a graph or any other method to solve.) It takes approximately seconds for the rocket to hit the ground. (Round to the nearest tenth.) Check Check for Understanding DELL