@Kitonum 

Thanks so mush for your help

 Thanks for helping me with Maple program

@Kitonum 

Thanks so mush for your help, thanks for taking your time and helping me with Maple program.

We have 44 equation like mw.file 

How can solve 44 equations        solving_linear_of_equations.mw

@Carl Love

Thanks for guiding me about LUDecomposition 

For example we have these equations, how can calculated the coeffitions by this method

@rlopez 

We use LUDecomposition method but this method not usefull for too long system of equations, for example 40*40 or 100*100

Thank you for guiding me 

@tomleslie 

Thanks for your helping me, it is true. 

Thanks so mush for your help.

Thanks for taking your time and helping me with Maple program.

I truly appreciate you to help me

Your program is true 
Excuse me, how can draw my figure like your figure
 My figure is 

@Markiyan Hirnyk 

Thanks so mush for your help.

How can I plot it?

Best wishes.

Sincerely,

Arman Shahsavan

@Markiyan Hirnyk 

when r is a function of theta, we expect f(r, theta) is shown by color in circle (nonsymmetric)  r=0.3..0.5*0.1*cos(theta) and theta=0..2*pi like this

Thanks so mush for your help.

plots:-densityplot(f, theta=0..2*Pi, r=r1 .. r2, coords=polar, colorstyle = HUE, style = patchnogrid);

By above program, first, initialize theta, the coordinate system seems to be in cartesian because the horizontal axis becomes the value for theta and vertical axis becomes the values for r.

when r is a constant we have figure below for my function f(r, theta), r=0.3..0.5 and theta=0..2*pi

In this figure, f(r, theta) is shown by color in circle (symmetric) in polar coordinate

when r is a function of theta, we expect f(r, theta) is shown by color in circle (nonsymmetric)  r=0.3+0.1*cos(theta)..0.5*0.1*cos(theta) and theta=0..2*pi like this

How can I plot it?