9514 1404 393
Answer:
[tex]\left[\begin{array}{ccc}0&3&4\\0&-7&1\end{array}\right][/tex]
Step-by-step explanation:
Reflection over the line y=-x swaps the coefficients and negates both of them.
(x, y) ⇒ (-y, -x)
Effectively, the coordinate matrix is pre-multiplied by ...
[tex]\left[\begin{array}{cc}0&-1\\-1&0\end{array}\right][/tex]
