Question

The equation of circle of radius 5 units touches the coordinates axes in the second quadrant is:

• A. x² + y² + 10x + 10y + 25 = 0
• B. x² + y² + 10x – 10y + 25 = 0
• C. x² + y² – 10x – 10y + 25 = 0
• D. x² + y² – 10x – 10y – 25 = 0

Answer 1

The correct option is B

x² + y² + 10x – 10y + 25 = 0

The coordinates of the centre of the required circle is (–5, 5) and radius is 5 units. The equation of circle is:

(x + 5)² + (y – 5)² = (5)²

⇒ x² + 25 + 10x + y² + 25 – 10y = 25

⇒ x² + y² + 10x – 10y + 25 = 0