sistem persamaan linear tiga variabel dengan metode eliminasi dan subtitusi Soal: x-y+z= -4 .......(1) 2x+y+2z= -5 .......(2) 3x-y-z= -6 ........(3)

x - y + z = -4
2x + y + 2z = -5
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-x -2y -z = 1

3x -y -z = -6
-x -2y -z = 1
--------------- -
4x +y = -7
y = -4x -7

x -y +z = -4
x +4x +7 +z = -4
5x +z = -11
5x = -z -11
x = -z-11/5

x -y + z = -4
-z-11/5 +4x +7 + z = -4
-z -11 +20x +35 +5z = -20
20x +4z +24 = -20
4z = -20x - 44
z = -5x -11