3x + 4y + 2=0 dan x + 3y -1=0 Selesaikan dengan metode substitusi

» 3x + 4y + 2 = 0
» x + 3y -1 = 0
x = 1 - 3y

3x + 4y + 2 = 0
3x + 4y = -2
3(1-3y) + 4y = -2
3 - 9y + 4y = -2
-5y = -5
y = 1

x + 3y -1 = 0
x + 3(1) -1 = 0
x +3-1 = 0
x +2 = 0
x = -2

Pembuktian
3x+4y+2=0
3x+4y+2=0
3(-2) + 4(1) +2 =0
-6+4+2 = 0
0=0
terbukti