Question 758679
x+y=7.........1
x-9y=-13......2
Subtract 1 from 2
 10y   =   20
   y   =   2
Substitute y = 2
in Eq (1)
x + y = 7
x + 2 = 7
    x = 7 - 2
    x = 5

 x = 5 y = 2
Hope this helps.
:-)