What's the gcf of the term 16x^3y^2+24x^2y

Julian wrote the following numeric pattern on the board3,10,17,24,31,38.what numbers of julian's pattern are compound numbers.

3.4a=57.8 what is the the value of a

36x2 + 49y2 = 1,764 the foci are located at: (-√13, 0) and (√13,0) (0, -√13) and (0,√13) (-1, 0) and (1, 0)edit: the answer is (- the square root of 13, 0) and (the square root of 13, 0)