Diketahu SPLTV {x+2z=3 3y+z=0 x-3y=-7 nilai dari x+y+z=

x+2z=3
3y+z=0 z = - 3y
x-3y=-7
Jawab :
x + 2z = 3
x + 2(-3y) = 3
x - 6y = 3

x - 6y = 3
x - 3y = - 7
_________-
- 3y = 10
y = - 10/3

x -3y= -7
x - 3(-10/3) = - 7
x = 30/3 = - 7
x = - 7 - 10
x = - 17

x + 2z = 3
(-17) + 2z = 3
2z = 3 + 17
2z = 20
z = 10


Maka nilai x + y + z = - 17 + - 10/3 + 10 = - 17 - 3.3 +10 = - 10.3