[tex]\left\{\begin{matrix}
y - \sqrt{2} x = 0\\
5x + \sqrt{8} y = 9\end{matrix}\right.[/tex]
[tex]y = 0 + \sqrt{2} x[/tex]
[tex]y = \sqrt{2} x[/tex]
[tex]5x + \sqrt{8} y = 9[/tex]
[tex]5x + \sqrt{8} \times \sqrt{2} x = 9[/tex]
[tex]5x +\sqrt{8 \times 2} x = 9[/tex]
[tex]5x + \sqrt{16} x = 9[/tex]
[tex]5x + 4x = 9[/tex]
[tex]9x = 9\:|\div9[/tex]
[tex]x=1[/tex]
[tex]y = \sqrt{2} x[/tex]
[tex]y = \sqrt{2} \times 1[/tex]
[tex]y = \sqrt{2} [/tex]
