If x2 + y2 + 6x + 5 = 4 (x – y) then (x

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If x² + y² + 6x + 5 = 4 (x – y) then (x – y) is

1. 1
2. –1
3. 0
4. 4

Correct Option: A

x² + y² + 6x + 5 = 4x – 4y
⇒ x² + y² + 6x – 4x + 4y + 5 = 0
⇒ x² + 2x + 1 + y² + 4y + 4 = 0
⇒ (x + 1)² + (y + 2)² = 0
∴ x + 1 = 0 ⇒ x = –1
y + 2 = 0 ⇒ y = –2
∴ x – y = –1 + 2 = 1