minta tolong dibantu, terimakasih

[tex]\displaystyle\left[\begin{array}{ccc}p&q\\q&p\end{array}\right]\left[\begin{array}{ccc}x\\y\end{array}\right]=\left[\begin{array}{ccc}p\\q\end{array}\right]\\\\\therefore\\px+qy=p|\times q|p^2x+pqy=p^2\\qx+py=q|\times q|\underline{q^2x+pqy=q^2}-\\~~~~~~~~~~~~~~~~~~~~~~~(p^2-q^2)x=p^2-q^2\\~~~~~~~~~~~~~~~~~~~~~~~x~~~~~~~~~~~~=1\\\\px+qy=p\\p(1)+qy=p\\qy=0\\y=0\\\\\therefore\\x+y=1+0\\\boxed{\boxed{x+y=1}}[/tex]