Question

Di ketahui = (1/x + 2/y =1)
(1/x + 4/z =0)
(1/y + 2/z = 1)

ditanya nilai x+y-z =

Answer 1

1/y + 2/z = 1
1/y = 1 - 2/z

1/x + 2( 1 - 2/z ) = 1 
1/x + 4/z             =0
2 - 4/z - 4/z = 1
-8/z = -1
z = 8

1/x + 4/z = 0
1/x + 1/2 = 0
1/x = -1/2 
x = -2

1/y + 2/z = 1
1/y + 1/4 = 1
1/y = 3/4
y = 4/3

x + y - z = -2 + 4/3 - 8
x + y - z = -26/3

Maaf jika ada salah perhitungan