Linear system/Simultaneous/1/Exercise

Solve the linear systems

${\begin{pmatrix}7&4\\1&2\end{pmatrix}}{\begin{pmatrix}x_{1}\\y_{1}\end{pmatrix}}={\begin{pmatrix}4\\9\end{pmatrix}},\,{\begin{pmatrix}7&4\\1&2\end{pmatrix}}{\begin{pmatrix}x_{2}\\y_{2}\end{pmatrix}}={\begin{pmatrix}6\\5\end{pmatrix}},\,{\begin{pmatrix}7&4\\1&2\end{pmatrix}}{\begin{pmatrix}x_{3}\\y_{3}\end{pmatrix}}={\begin{pmatrix}-2\\5\end{pmatrix}}$

simultaneously.

Create a solution