How do you simplify #4a + 7 + 2a#?
Consider money for a moment. I am English so I am going to use £
Suppose you had 4 lots of £5 notes in your wallet. You then added a further 2 lots of £5 notes. The total lots of £5 would be 4+2.
Ok, we are using the letter 'a' but the same principle applies.
So we have
This is the same as
The actual value of