matlab解带已知参数的方程组怎么解？？？？

function y = mysolve1(m,n) syms a b x z [a,b,x,z]=solve(a+x+z-m,b+x+2*z-n,z-2140000*a*b^2,x-a*b*764000) a = double(a) b = double(b) x = double(x) z = double(z) end