mohon dibantu kak,,,

3x+y=11 [.5] 15x+5y=55
5x-y=13 [.3] 15x-3y=39 _
8y=16
y=2
3x+y=11
3x+2=11
3x=11-2
3x=9
x=9/3
x=3

Jadi, {(x,y)} adalah {(3,2)}

1) 3x + y = 11
5x - y = 13
----------------- +
8x = 24
x = 3

3x + y = 11
3(3) + y = 11
y = 2

{(3, 2)}

2) 2x + 3y = 16
2x + y = 12
--------------------- --
2y = 4
y = 2

2x + y = 12
2x + 2 = 12
2x = 10
x = 5

x + y = 5 + 2 = 7