Two numbers x and y (x > y) are such that their sum is equal

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Two numbers x and y (x > y) are such that their sum is equal to three times their difference.
Then value of 3xy will be:
2(x² − y²)

(x + y) = 3 (x – y) = 3x – 3y
⇒ 3y + y = 3x – x
⇒ 2x = 4y
⇒ x = 2y

⇒	x	=	2
	y		1

∴ x = 2, y = 1

3xy	=	3 × 2 × 1	=	6	= 1
2(x² − y²)		2 × (4 − 1)		6

Then value of	3xy	will be:
	2(x² − y²)