Kim's teacher has marked this problem as one to recheck, but Kim cannot determine what she has done incorrectly. Identify Kim's error and write a correct solution.
Six less than 2 times a number is 50. What is the number?
2x – 6 = 50 (line 1)
2x – 6 – 6 = 50 – 6 (line 2)
2x = 44 (line 3)
2x ÷ 2 = 44 ÷ 2 (line 4)
x = 22 (line 5)