I am currently doing a course on Computer Graphics Algorithms. This involves lot of matrix transformations i.e. for eg - rotating co-ordinates, translating, reflecting etc. I am solving the problems on paper using a calculator, but I need some software which will help me verify the solution (the calculations are very error prone with so many matrix multiplications) i.e. I am looking for software where if I input "Reflect point (4,5) on line y = 3x + 12", it will give me the reflected co-ordinates. Does anyone know of any free software which will help me with this?