SPLTV
HP

misal
a = 1/x, b= 1/y, c= 1/z

1/x+1/y+1/z=2 ⇒ a + b + c = 2  . . . (i)

3/x-1/y+2/z=-1 ⇒ 3a - b + 2c = - 1  . .  (ii)

1/x+1/y-1/z=4 ⇒  a + b - c = 4 . . . . . (iii)

eliminasi i dan iii
a +  b + c = 2
a + b - c =  4 __(+)
2a + 2b = 6
a + b = 3 . . . . (iv)

eliminasi  i dan ii
a +  b + c = 2 . . .  (kali 2)
3a - b + 2c = 1

2a+ 2b + 2c= 4
3a - b + 2c = 1  ___ (-)
-a + 3b = 3 . . .  (v)

eliminasi iv dan  v
a + b = 3
-a + 3b = 3 ___(+)
4b =  6
b =  6/4 = 3/2

a+ b = 3
a=  3 - b
a=  3 -3/2
a= 3/2

a +  b + c = 2
3/2 + 3/2 + c = 2
3 + c = 2
c= -1

a= 3/2  maka x  = 2/3
b= 3/2  maka y =  2/3
c=  1   amaka  z =  1

nilai  dri  x + 2y - 3z =
= 2/3 + 2 (2/3) - 3(1)
= 2/3 + 4/3 - 3
= 6/3 - 3
= 2 - 3
= - 1