Question

Persamaan linear dua variabel 2x+2y=-2 x+3y=1

Answer 1

2x +2y = -2 ....... (P1)
x +3y = 1
x = 1 -3y ............(P2)

gantikan P2 ke dalam P1,
2x +2y = -2
2(1 -3y) +2y = -2
2 -6y +2y = -2
4y = 4
y = 1

gantikan y = 1 ke dalam P2,
x = 1 -3y
x = 1 -3(1)
x = 1 -3
x = -2

Answer 2

2x + 2y = -2 x1
x + 3y = 1 x2

eliminasi
2x + 2y = -2
2x + 6y = 2
-4y = -4
y = -4/-4
y = 1

subtitusi
2x + 2y = -2
2.1 + 2y = -2
2 + 2y = -2
2y = -2 - 2
2y = -4
y = -4/2
y = -2

hp ( 1,-2 )