The cables of a suspension bridge are in the shape of a parabola. The

Question

towers supporting the cables are 600 feet apart and 80 feet high. If the
cables touch the road surface midway between the towers, what is the
equation of the cables?

Answer 1

Since the vertex is at (0,0), let the parabola be
y = ax^2
since y(300) = 80, a = 80/300^2