If the sum of two numbers is 3 and the sum of their squares

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If the sum of two numbers is 3 and the sum of their squares is 12,then their product is equal to :

Let two numbers be x and y.
x + y = 3
x² + y² = 12
⇒ (x + y)² = (3)²
⇒ x² + y² + 2xy = 9
⇒ 12 + 2xy = 9
⇒ 2xy = − 3

⇒ xy = −	3
	2