Question

Deanna is adjusting a satellite because she finds it is not focusing the incoming radio waves perfectly. The shape of her satellite can be modeled by mc016-1.jpg, where x and y are modeled in inches. She realizes that the static is a result of the feed antenna shifting slightly off the focus point. What is the focus point of the satellite?
(–3, 0)
(0, –3)
(0, 3)
(0, 4)

Answer 1

The parabola is x^2 = 12y, which is of the form x^2 = 4py with 4p = 12 so p = 3. Thus the focus is (0, 3).