Tentukan himpunan penyelesaian dari sistem persamaan berikut dengan metode subsitusi dan eliminasi

a) x + y = 2
x - y = 8
------------------(+)
2x = (-6)
x = - 3
x + y = 2
- 3 + y = 2
y = 2 + 3
y = 5
hp = {-3,5}

b) 2x - 3y = 6
x - y = 1 |×2
2x - 3y = 6
2x - 2y = 2
-----------------(-)
- y = 4
y = - 4
x - y = 1
x + 4 = 1
x = 1 - 4
x = - 3
hp = {-3,-4}

c) x - 2y = 5
x + y = 11
------------------(-)
- 3y = - 6
y = 2
x + y = 11
x + 2 = 11
x = 11 - 2
x = 9
hp = {9,2}

d) 3x - 2y = 5 |×3
4x + 3y = 6 |×2
9z - 6y = 15
8x + 6y = 12
-------------------(+)
17x = 17
x = 1
3x - 2y = 5
3(1) - 2y = 5
- 2y = 5 - 3
y = 2 ÷ (-2)
y = -1
hp = { 1,-1}