The difference between factorization and expansion
An example of factorization could be
where it is clearly shown that the common factor of both 6c and -30, 3, is moved to the outside of the parentheses, hence the term factorization.
Expansion is almost the opposite of factorization. For example,
the parentheses are removed, 3a and 6 are multiplied by 2.
Hence, factorization is then process of removing factors from and equation, while expansion is multiplying the equation in the parentheses (eg. in the example for expansion, 3a+6) by the factor outside the parentheses