The arch support of a bridge can be modeled by y=-0.0012x^2 where x and y are measured in feet. Find the height and width of the arch.

Question

I don't know how to even attempt to solve this... If you know how, can you PLEASE help asap!!

Answer 1

This cannot be right, as the vertex is at (0,0)
You need an equation of the form
y = a - bx^2
where the height of the arch is at a, and the width is 2√(a/b)

Answer 2

height: 300 feet
width: 1000 feet

Answer 3

WIDTH: 342941 :HEIGHT: 243143