Answer: x= -189, y =252
Explanation:
Let the first number be x and second number be y
so
x + y = 63
x = 63-y
now
1/9 of x + 1/6 of y = 21
x/9 + y/6 = 21
substituting x's value from equation i
(63-y)/9 + y/6 = 21
(378-6y+9y)/54 = 21
378+3y = 1134
3y = 1134-378
so, 3y = 756
so, y = 756/3
so, y = 252
now
x = 63-252
so, x = -189