Interactions
Q: Let A be a square 2×2 matrix. The linear transformation x?Ax maps R2 to R2. Create an interaction that shows the effect of applying A to the unit square. Draw two images: the plane before the linear transformation (showing the unit square and colored basis vectors) and the plane after the linear transformation (showing the image of the unit square under A and the image of the basis vectors). It may be useful to use the "graphics array" to show two plots next to each other. In the interact, allow the user to enter 4 values that are the entries of the 2×2 matrix A.
How can I go about this?
Do you understand the question ?
Sounds like a combination of [this](http://interact.sagemath.org/node/29) and [that](http://interact.sagemath.org/node/20).