The equation x² + y² + 4x - 6y + 9 = 0 represents a circle with radius:
Question 1
Q1. The equation x² + y² + 4x - 6y + 9 = 0 represents a circle with radius:
Answer: √2
Explanation: Complete the square: radius r = √[(2)² + (3)² - 9] = √2.