Hello! In order to solve this problem, you must subtract 5x from both sides to get 20 by itself. When you do that, you get 4x = 20. Now, divide each side by 4 to isolate the "x". When you do, you get x = 5. Your error had to have been that you added 5x into 20, but those numbers are not like terms. That's how you got an odd number. The answer is x = 5.
