Practice Test 3

A linear transformation is represented by $$D=\begin{pmatrix}-1&0\0&1\end{pmatrix}.$$ The unit square is shown on the coordinate plane. Which claim about area scaling is correct?

On the coordinate plane, the segment from $(-2,1)$ to $(2,1)$ is shown. A transformation $T$ is defined by the matrix $$I=\begin{pmatrix}1&0\0&1\end{pmatrix}.$$ Which transformation does the matrix represent?