Identify set of {-2,-1,0,1,2}

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Find the solution(s) to x^2-14+49=0

What are the greatest common factor of 75 and 30