Question

Explain the steps necessary to find the center and radius of the circle below. x2 + 4x + y2 ‒ 6y = 9 Then, find the center and the radius of this circle and sketch the graph of the circle.

Answer 1

The necessary step to find the center and radius is complete the square so it is in the format (x - h)² + (y - k)² = r²

x² + 4x + (4) + y² - 6y + (9) = 9 + (4) + (9)
→ (x + 2)² + (y - 3)² = 22

Center: (-2, 3)
radius: √22