After Summer vacation, I came to school and started to teach Algebra
in Class 8. As I was going through I realized that students haven’t understood
the knowledge on rearranging like and unlike terms. First day, I just gave
them, what my teacher did. On that day, I found that most of the girls and few
boys were shifting the numbers to their respective like terms but they were
leaving the signs which were in front of those terms.
For instance, to solve this expression 2a+3b-a-2b. First, we need
to arrange the like terms by 2a-a+3b-2band
lastly it gives a+b. Instead, they were doing 2a+a-3b-2b which give the wrong answer
of 3a-5b.