Answer:
The mistake happens in the 4th line.
Step-by-step explanation:
The first 3 lines are correct until the 4th line which is 2=6x. This is wrong. If we go back a line to the third line, it is 22=-20+6x. The part that was wrong was that they subtracted 20 from 22 to get 2. We are supposed to add 20 to each side because the -20 is negative. So the 4th line should be 42=6x. Then, we know that 6 times 7 is 42, so x is equal to 7.
22 + 53x + x = -20 + 60x
22 + 54x = -20 + 60x
22 = -20 + 6x
42 = 6x
x = 7
