tentukan penyelesaian sistem persamaan berikut dengan metode eliminasi !a.x+2y=-1 dan 2x+y=8 , b.3x+4y+2=0 dan x+3y-1=0

a) x + 2y = - 1 |×2
2x + y = 8
maka
2x + 4y = - 2
2x + y = 8
-----------------(-)
3y = - 10
y = - 10/3
x + 2y = - 1
2x + y = 8 |×2
maka
x + 2y = - 1
4x + 2y = 16
------------------(-)
- 3x = - 17
x = 17/3
hp = { 17/3 , - 10/3 )

b) 3x + 4y = - 2
x + 3y = 1 |×3
maka
3x + 4y = - 2
3x + 9y = 3
-------------------(-)
- 5y = - 5
y = 1
3x + 4y = - 2 |×3
x + 3y = 1 |×4
maka
9x + 12y = - 6
4x + 12y = 4
---------------------(-)
5x = - 10
x = - 2
hp = { - 2 , 1 }