[tex]y = - 2x + 53x - 4y = 2 \\ y = 51x - 4y = 2 \\ > y = 51 x - 4y \\ > 51x - 4y = 2[/tex]
[tex]y = 51x - 4y \\ 5y = 51x \\ y = \frac{51}{5} x[/tex]
Substitute 51/5x into
[tex]51x - 4( \frac{51}{5} x) = 2 \\ 51x - 40.8x = 2 \\ 10.2x = 2 \\ x = 2 \times \frac{10}{102} \\ x = \frac{10}{51} \: aka \: 0.196[/tex]
Substitute that into
[tex]y = \frac{51}{5} \times \frac{10}{51} \\ y = 2[/tex]
Hope this helps. Answer should be correct. Unless your quadratic equation is wrongly stated.