metode substitusi { 2× + y = 1 } { × - 5y = -27 }

2x + y = 1    ║ x1    => 2x+y = 1
x - 5y = -27  ║x2    => 2x - 10y = -54 (eliminasi x)

11y = 55
y = 55/11 = 5

Subtitusi ke salah satu nya
2x + y = 1
2x + 5 = 1
2x = 1-5
2x= -4
x = -4/2
x= -2

jadi x = -2, y = 5