Answer: The error is in step 3
Step-by-step explanation:
In step 2, they multiplied both sides by 8 to clear out the fractions. In step 3, they forgot to distribute the 8 to each term inside the parenthesis.
This is what the steps should look like

In step 4, we added 8 to both sides. Afterward, divide both sides by 3 to fully isolate x.
The improper fraction 13/3 is the same as the mixed number 4 & 1/3.