In a factory, a parabolic mirror to be used in a searchlight was placed on the floor. It measured 40 centimeters tall and 90 centimeters wide. Find the equation of the parabola.

Question

I tried working this problem out and I got y=-8/405x^2+40, but I'm not sure if it is right. Could someone please help me?

Answer 1

draw a picture of the parabola, centered over (0,0)

vertex: (0,40)
x-intercepts: x = 45, -45

y = (45^2 - x^2) * 40/45^2

you can pretty it up if you want.

Answer 2

Is my answer correct then??