x+y+z=1 2x-y+3z=2 2x-y-z=2 HP persamaan tersebut yaitu

Harus paham dulu ini...
- x - = +
+ x - = -
- x + = -
+ x + = +

x+y+z=1 dikali 3
2x-y+3z=2 diakli 1

3x+3y+3z=3
2x-y+3z = 2
____________-
x+4y = 1

2x-y+3z=2 dikali 1
2x-y-z=2 dikali 3

2x-y+3z =2
6x-3y-3z =6
____________+
8x-4y = 8

x+4y=1
8x-4y=8
_______+
9x = 9
x = 1

x+4y =1
1+4y =1
4y = 1-1
4y = 0
y = 0

2x-y-z=2
2(1)-0-z = 2
z = 0

(x, y dan z = 1,0 dan 0)




x +3 <= 2x - 3
x-2x <= - 3-3
-x <= - 6
x >= 6