A circle is defined by the equation (x - 2)² + (y + 1)² = 9. What is the area of the circle?
Correct: C
The equation of a circle is (x - h)² + (y - k)² = r², where (h, k) is the center and r is the radius. In this case, r² = 9, so r = 3. The area of the circle is πr² = π(3²) = 9π.