Given, two numbers differ by 3.

Let one of the numbers be ‘a’.

Second number = a – 3

Also, their product is 504.

⇒ a(a – 3) = 504

⇒ a² – 3a – 504 = 0

⇒ a² – 24a + 21a – 504 = 0

⇒ a(a – 24) + 21(a – 24) = 0

⇒ (a + 21)(a – 24) = 0

⇒ a = -21, 24

Thus numbers are -21, -24 or 24, 21