If matrix $A=\left[\begin{array}{ll}3 & x \\ y & 0\end{array}\right]$ and A' = A, then : |
x = y x = 0, y = 3 x = 3, y = 0 x + y = 3 |
x = y |
$A=\left[\begin{array}{ll}3 & x \\ y & 0\end{array}\right]$ given A' = A $A'=\left[\begin{array}{ll}3 & 0 \\ x & y\end{array}\right]$ interchange rows with columns $\Rightarrow \left[\begin{array}{ll}3 & x \\ y & 0\end{array}\right]=\left[\begin{array}{ll}3 & y \\ x & 0\end{array}\right]$ So x = y |