himpunan penyelesaian dari sistem 4x+7y= -13 dan 7x+4x= 2

4x + 7y = -13. (4) 16x + 28y = - 52
7x + 4y = 2. (7) 49x + 28y = 14

-33x = - 66
x = -66 : -33
x = 2


4x + 7y = -13
4(2) + 7y = -13
8 + 7y = -13
7y = -13-8
7y = -21
y = -21 : 7
y = -3