Solving system of 4 equation

I need assistance with solving these 4 equations in MATLAB as I am unsure of how to code them. Can someone please help me? It's worth mentioning that all variables, except for e1, e2, e3, and e4, are known, and K(i), k2(i), k3(i), and k4(i) are matrices consisting of 25 values.

0=((nco+v3*e1+v22*e2+v41*e4)^2*(nh2+v4*e1+v24*e2+v33*e3)^2)-(k(i)*(n0+v*e1+v03*e3+v04*e4)^2*(nch4+v1*e1+v31*e3)*(nco2+v2*e1+v23*e2+v42*e4));
0=((nco+v3*e1+v22*e2+v41*e4)*(nh2o+v21*e2)-(k21(i)*(nco2+v2*e1+v23*e2+v42*e4)*(nh2+v4*e1+v24*e2+v33*e3)));
0=((nh2+v4*e1+v24*e2+v33*e3)^2-(k31(i)*(n0+v*e1+v03*e3+v04*e4)*(nch4+v1*e1+v31*e3)));
0=((n0+v*e1+v03*e3+v04*e4)*(nco2+v2*e1+v23*e2+v42*e4)-(k41(i)*(nco+v3*e1+v22*e2+v41*e4)^2));

Answer 1

[Torsten]

Try "fsolve":

e0 = [e10;e20;e30;e40];   % initial guesses
for i = 1:25
    fun = @(e1,e2,e3,e4) [((nco+v3*e1+v22*e2+v41*e4)^2*(nh2+v4*e1+v24*e2+v33*e3)^2)-(k(i)*(n0+v*e1+v03*e3+v04*e4)^2*(nch4+v1*e1+v31*e3)*(nco2+v2*e1+v23*e2+v42*e4));...
                          ((nco+v3*e1+v22*e2+v41*e4)*(nh2o+v21*e2)-(k21(i)*(nco2+v2*e1+v23*e2+v42*e4)*(nh2+v4*e1+v24*e2+v33*e3)));...
                          ((nh2+v4*e1+v24*e2+v33*e3)^2-(k31(i)*(n0+v*e1+v03*e3+v04*e4)*(nch4+v1*e1+v31*e3)));...
                          ((n0+v*e1+v03*e3+v04*e4)*(nco2+v2*e1+v23*e2+v42*e4)-(k41(i)*(nco+v3*e1+v22*e2+v41*e4)^2))];
    sol(i,:) = fsolve(@(x)fun(x(1),x(2),x(3),x(4)),e0);
end

[nima]

Thanks for your response but I think these equations have more than one answers for each unkonwn variables. How can I find and see the other answers?

[Torsten]

You can try different initial values for the unknowns and MultiStart, but there is no guarantee to find all solutions.