The Sum of two number is 15 and sum of their square is 113. The numbers are?

Let the number be x and (15-x)
Then, x² + (15 - x)²= 113
⇒ x² - 15x + 56 = 0
⇒ (x-7) (x-8) = 0
∴ x = 8 or x = 7
So, the numbers are 7 and 8