By the binomial theorem,

I assume you meant to say "independent", not "indecent", meaning we're looking for the constant term in the expansion. This happens for k such that
12 - 3k = 0 ===> 3k = 12 ===> k = 4
which corresponds to the constant coefficient

Since y=2x+1 does not pass through the origin (i.e. there exists the constant term of 1 ), the variables y and x are not directly proportional - though, they do have a linear relationship.
Answer:
Salim can simplify that and the answer will be 
Step-by-step explanation:
This is because of the law of multiplying powers, which states that you can add the exponents if the base is the same. So, you just add m and n and put that as the exponent and you will have the answer.