Answer:
We have two numbers, let's call them A and B.
We know one number is 9 more than the other, which we can write as the following expression:
A + 9 = B
We also know the product of these numbers is 252, which we can write as the following expression:
A*B=252
Since we know B is equal to 'A+9', we can then sub 'A+9' in for B in the second expression and then use factorisation to find a value for A:
A*B=252
A(A+9)=252
A²+9A-252=0
(A+21)(A-12)=0
A=-21 0r A=12
If A = -21, then B= -21 +9 = -12
If A = 12, then B = 12+9 = 21
Therefore, these numbers are either 12 and 21, or -21 and -12.
Hope this helps, let me know if you want certain parts explained more :)