So we need to find the solutions to the equation (x+6)y=9 so we can arrange them in pair (x,y). We simply plug in the numbers into the equation. First pair (-5,9), we get (-5+6)9=9 so 1=1 and that is true, so first pair works. Second pair: (-3+6)3=9 we get (3)3=9 and 9=9 so second pair also works. Third pair: (3+6)1=9 we get 9=9, also works. Fourth pair: (7+6)9=9 we get 13*9=9 and 117=9 which is false so the fourth pair can't be a solution for the equation. The correct answers are A, B and C.