Tentukan x+y+z jika 3/x + 5/y = 2 , 4/x + 2/z = 2 , 1/y - 4z = -7

[tex] \frac{3}{x} + \frac{5}{y} = 2[/tex]
[tex] \frac{4}{x} + \frac{2}{z} = 2[/tex]
[tex] \frac{1}{y} - \frac{4}{z} = - 7[/tex]