Question

Why can you not combine the 8a2 and 8a?

Answer 1

you can't add or subtract numbers that don't have the same variable or the same exponent

Answer 2

You cannot combine the terms
`8a^2` and
`8a` because they are not like terms, which are terms that consist of both the same power, and the same variable. Seen with the two terms given, they both share the same variable (
`a`), but not the same power (
`2`).