024 MATLAB The differential equation

The differential equation

a=0.18;
b=0.06;
K=2600;
W=200;

x=linspace(-0.5,0.5,1000000);
L0=sqrt(a^2+b^2);
L=sqrt(a^2+(b+x).^2);
y=2*K*(L-L0).*(b+x)./L+(K*x)./2-W;
plot(x,y) 

[p,q]=fzero('(2*2600*(sqrt(0.18^2+(0.06+x)^2)-sqrt(0.18^2+0.06^2)))*(0.06+x)/sqrt(0.18^2+(0.06+x)^2)+(2600*x)/2-200', 0)