Van = facebook.com/LearningCalculus;

f(x,m):= 2*x^2-(3+8*%i)*x-(m+4*%i) = 0$

a:realpart(f(x,m));b:imagpart(f(x,m));

solve(a,x);
solve(b,x);

roots:substitute(-(1/2),x,solve(a,x));

solve(first(roots),m);

substitute(2,m,solve(a,x));

f(x,2);

realpart(f(x,2));

imagpart(f(x,2));