Exercise 7

By what factor does each transformation change the size of boxes?

• (a)  $\begin{pmatrix}x\\ y\end{pmatrix}\mapsto\begin{pmatrix}2x\\ 3y\end{pmatrix}$     (b)  $\begin{pmatrix}x\\ y\end{pmatrix}\mapsto\begin{pmatrix}3x-y\\ -2x+y\end{pmatrix}$     (c)  $\begin{pmatrix}x\\ y\\ z\end{pmatrix}\mapsto\begin{pmatrix}x-y\\ x+y+z\\ y-2z\end{pmatrix}$