Question

A skateboard halfpipe is being designed for a competition. The halfpipe will be in the shape of a parabola and will be positioned above the ground such that its focus is 20 ft above the ground. Using the ground as the x-axis, where should the base of the halfpipe be positioned? Which equation best describes the equation of the halfpipe?
(0, 20); y equals one over eighty times x squared plus 20
(0, 20); y equals one over eighty times x squared minus 20
(0, 10); y equals one over forty times x squared plus 10
(0, 10); y equals one over forty times x squared minus 10

Answer 1

Answer:

Option A , (0, 20); y equals one over eighty times x squared plus 20

Step-by-step explanation:

The equation of parabola is given by  

(X-h)^2 = 4p(Y-k)^2

In this case h = 0

So we get  

Y = X^2/4P +k

Focus point is (h, p+k) , p+k = 40

Hence h, k = (0,20)

P = 40-k = 20

Equation Y = X^2/80 +20

Hence, option A is correct

Answer 2

Answer: (0, 20); y equals one over eighty times x squared plus 20

Step-by-step explanation: took the test