|x - 1| + |2x - 6| = 12
+) Nếu x < 1, ta có:
1 - x + 6 - 2x = 12
=> 7 - 3x = 12
=> 3x = 7 - 12 = -5
=> x = -5/3 (TM)
+) Nếu 1 \(\le\)x < 3, ta có: x - 1 + 6 - 2x = 12
=> 5 - x = 12
=> x = 5 - 12 = -7 (không TM)
+) Nếu x\(\ge\) 3, ta có: x - 1 + 2x - 6 = 12
=> 3x - 7 = 12
=> 3x = 12 + 7 = 19
=> x = 19/3 (TM)
Vây x = -5/3; x = 19/3