1. 10.2 Circles
Objective:
Use and determine the standard and general forms of the equations of a circle.
Graph Circles.

2. Standard Form of a Circle
The standard form of the equation of a circle with radius r and center at (h, k) is: (x – h)2 + (y – k)2 = r2

3. Write the standard form of the equation of the circle that is tangent to the x-axis and has its center at (3, -2). Then graph the equation.

4. Write the standard form of the equation of the circle that is tangent to the x-axis and has its center at (-4, 3). Then graph the equation.

5. General Form of a Circle
The standard form of the equation of a circle is: x2 + y2 + Dx + Ey + F = 0 where D, E, and F are constants.

6. The equation of a circle is x2 + y2 – 4x + 12y + 24 = 0
The equation of a circle is x2 + y2 – 4x + 12y + 24 = 0. a) Write the standard form of the equation. b) Find the radius and the center. c) Graph the equation.

7. The equation of a circle is 2x2 + 2y2 – 4x + 12y – 18 = 0
The equation of a circle is 2x2 + 2y2 – 4x + 12y – 18 = 0. a) Write the standard form of the equation. b) Find the radius and the center. c) Graph the equation.

8. Write the standard form of the equation of the circle that passes through the points at (1, -1), (5, 3), and (-3, 3). Then identify the center and radius of the circle.

9. Write the standard form of the equation of the circle that passes through the points at (5, 3), (-2, 2), and (-1, -5). Then identify the center and radius of the circle.

10. Assignment
10.2 Practice Worksheet #1-5