Question

a golfer needs to hit a ball a distance of 500 feet, but there is a 60-foot tall tree that is 100 feet in front of the point where the shot needs to land. given that the maximum height of the shot is 120 feet, and that the intended distance of 500 feet is reached, by how much did the ball clear the tree?

Answer 1

We can create a parabola equation of the trajectory using the vertex form:

y = a (x – h)^2 + k

 

The center is at h and k, where h and k are the points at the maximum height so:

h = 250

k = 120

 

Therefore:

 y = a (x – 250)^2 + 120

 

At the initial point, x = 0, y = 0, so we can solve for a:

0 = a (0 – 250)^2 + 120

0 = a (62,500) + 120

a = -0.00192

 

So the whole equation is:

y = -0.00192 (x – 250)^2 + 120

 

So find for y when the golf ball is above the tree, x = 400:

y = -0.00192 (400 - 250)^2 + 120

y = 76.8 ft

 

So the ball cleared the tree by:

76.8 ft – 60 ft = 16.8 ft

 

 

Answer:

16.8 ft