Question

semiellipse

Answer 1

A railroad tunnel is shaped like a semiellipse as shown below.


The height of the tunnel at the center is 54 ft and the vertical clearance must be 18 ft at a point 8 ft from the center. Find an equation for the ellipse.

Answer 2

what does '18 ft at a point 8 ft' mean?

Answer 3

X^2/A^2 + Y^2/B^2 = 1
8^2/A^2 + (18/54)^2 = 1
64/A^2 = 1 - 1/9 = 8/9
and then what do i do?

Answer 4

please :/ @Luigi0210 @mathmale @hartnn