How can I incorporate the "s" symbolic variable in multiplication?

Okay so this is a simple code for a simple closed loop control system:

sys=tf(1,[1 2 2]);
syms s
ctr=4+(3/s);
e_cl=feedback(1,sys*ctr);
u_cl=feedback(ctr,sys);
y_cl=feedback(sys*ctr,1);
step(e_cl,'b',u_cl, 'r',y_cl, 'g')
[num,den]=tfdata(y_cl,'v');
roots(den);
stepinfo(y_cl);

When I run it, it gives me an error for the e_cl equation saying: "Invalid operand. Variables of type "sym" cannot be combined with other models."

This makes sense to me, since "s" is symbolic you cannot multiply numbers. Any idea how I can make this work? s is the laplace variable so making it a vector wouldn't work with finding the step responses. I need to somehow make "ctr=4+3/s" into a function where I can multiply it by sys. Thanks!

[Walter Roberson]

Duplicates http://www.mathworks.com/matlabcentral/answers/315257-how-can-i-incorporate-the-s-symbolic-variable-in-multiplication