Alec simplified the expression below. He then checked his work by substituting 3 for x. He noticed his two values were not equal. The expression gave him an answer of 27, and the simplified expression gave him an answer of 28.
What was Alec's error when simplifying?

When y’all answer can y’all explain too !

The perimeter of a quarter circle is 14.28 miles. what is the quarter circle's radius?

Alocal hamburger shop sold a combined total of 601 hamburgers and cheeseburgers on friday. there were 51 more cheeseburgers sold than hamburgers. how many hamburgers were sold on friday? a local hamburger shop sold a combined total of hamburgers and cheeseburgers on friday. there were more cheeseburgers sold than hamburgers. how many hamburgers were sold on friday?