How can I draw the cable using MATLAB script? The parabola needs to terminate at the poles.

My code here draws out the poles but I can't figure out how to do the curve. The sample numbers we were given was x = 50, ymin = 8, y = 15.

x1 = x;

x2 = -x;

x3 = 0;

y1 = y;

A = [x,x]

B = [0,y1]

C = [x2,x2]

D = [0,y1]

plot (x,y,'k:.', x2,y,'k:.',x3,ymin,'k:.')

axis([-2*x,2*x,0,2*y])

line (A,B)

line (C,D)

Pole Cable Pole C:\Docu Docume