pliss kakk bantu jawab..mohon bantuan nya ya kak

[tex]dik \: x = y {}^{2} [/tex]
[tex] \: \: \: \: \: \: \: 4 = y {}^{2} + x - 2y[/tex]
[tex]dit \: x \: y[/tex]
4 = y ^2 + x - 2y
4= y^2+ y^2-2y
4= 2y^2-2y