Question

Diketahui sistem persamaan 2/x + 1/y = 1 dan 1/x - 2/y = 8. Nilai dari 1/x+y ?
a. 1/3
b. 1/4
c. 1/5
d. 1/6
tolong dijwb bsrta caranya

Answer 1

2/x + 1/y = 1  ................(1)
2/x - 4/y = 16-  ..............(2)
         5/y = - 15
y = 5/-15 = - 1/3
Pers (1)   
2/x + 1/(-1/3) = 1
2/x - 3 = 1
2/x = 4
x = 2/4 = 1/2

1/(x+y) = 1/(1/2 - 1/3)
             = 1/(1/6)
             = 6
1/x + y = 1/(1/2) - 1/3
           = 2 - 1/3
           = 5/6