Symbolic package for Octave

[Pervin, William]

I want to have my students use Octave in my Linear Algebra class and not have 
to buy MATLAB.
So far I am able to install Octave so they should be able to do it also. We all 
use WINDOWS!
I want to install the Symbolic package and don't know how. I have downloaded a 
file named:
"symbolic-2.2.1.tar.gz" and put it everywhere I can find 
(octave,share,packages,octave-packages, etc.) 
and then do a "pkg install symbolic-2.2.1.tar.gz" as the documentation seems to 
say. I get the
message "warning: file symbolic-23.2.1.tar.gz" does not exist". What is the 
correct, detailed way
to install the Symbolic package? BTW, I don't even know what a .tar.gz file is 
(maybe zipped?)
and I obviously don't know where to put it. Please give me some detailed 
instructions written
for an Idiot. 

Thanks,
 

Dr. William J. Pervin

Professor Emeritus of Mathematics,
Electrical and Computer Engineering,
and Computer Science
University of Texas at Dallas