The origin of the coordinate plane is taken at the vertex of the arch in such a way that its vertical axis is along the positive y-axis. This can be diagrammatically represented as
The equation of the parabola is of the form x2 = 4ay (as it is opening upwards).
It can be clearly seen that the parabola passes through point (5/2,10)
Therefore, the arch is in the form of a parabola whose equation is X2 =5/8y
Hence, when the arch is 2 m from the vertex of the parabola, its width is approximately 2.23 m.
