# calculus

posted by
**Don**
.

I need help with this problem: The path traveled by a golf ball with a 9-iron can be modeled with the quadratic equation, y= -0.042xsquared + 5x, where x is the distance in yards from the point it was hit and y is the height of the golf ball in feet. Assume that the ground is level.

a. Find the maximum height reached by the ball.

b. How far from where it was hit does the ball hit the ground?

I really need to understand this, so please show the work. Any help you can give would be greatly appreciated.