Tentukan Harga X pada persamaan berikut

1. -3x - 3x = 4x +8
-3x -4x = 8+3
-7x. = 11
x. = 11/-7

2. 13-2x = 9x
13. = 9x+2x
13. = 11x
13/11. = x

3. 2x-4 = 31
2x.= 31 +4
2x = 35
x = 35/2
x = 17,5

4. 12-x = 3
12-3 = x
9= x