Where plots intersect of two equations plotted using ezplot.

I have two equations of the form: eqn11= 'a(1,1)-b(1,1)+a(2,1).*y+a(3,1).*y.^2+a(4,1).*y.^3+a(5,1).*x+a(6,1).*x.*y+a(7,1).*x.*y.^2+a(8,1).*x.*y.^3+a(9,1).*x.^2+a(10,1).*x.^2.*y+a(11,1).*x.^2.*y.^2+a(12,1).*x.^2.*y.^3+a(13,1).*x.^3+a(14,1).*x.^3.*y+a(15,1).*x.^3.*y.^2+a(16,1).*x.^3.*y.^3'; eqn12= 'a(1,2)-b(1,2)+a(2,2).*y+a(3,2).*y.^2+a(4,2).*y.^3+a(5,2).*x+a(6,2).*x.*y+a(7,2).*x.*y.^2+a(8,2).*x.*y.^3+a(9,2).*x.^2+a(10,2).*x.^2.*y+a(11,2).*x.^2.*y.^2+a(12,2).*x.^2.*y.^3+a(13,2).*x.^3+a(14,2).*x.^3.*y+a(15,2).*x.^3.*y.^2+a(16,2).*x.^3.*y.^3'; a and b are matrix's of constants. How do I find where they intersect?

Thank you.