Q4 of 242 Page 9

The sum of two numbers is 48 and their product is 432. Find the numbers.

Let the numbers be ‘a’ and ‘b’.

Given, sum of two numbers is 48 and their product is 432.

⇒ a + b = 48

⇒ a = 48 – b

Also, ab = 432

⇒ 48b – b² = 432

⇒ b² – 48b + 432 = 0

⇒ b² – 36b – 12b + 432 = 0

⇒ b(b – 36) – 12(b – 36) = 0

⇒ (b – 12)(b – 36) = 0

⇒ b = 12, 36

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