1. SECTION 10.8 – EQUATIONS OF
CIRCLES

2. EQUATIONS OF CIRCLES
 How do I write the equation of a circle?
 How do I graph a circle on the coordinate plane?

3. CIRCLE
 Circle: A circle is the locus of points in a plane
equidistant from a given point.

4. EQUATION


5. EQUATION


6. CENTER

7. EXAMPLES
Write an equation for a Write an equation for a
circle with the center at (3, circle with the center at (–
–3), d = 12. 12, –1), r = 8.

8. GRAPH

9. GRAPH

10. HOMEWORK
 Worksheet

11. LESSON PLAN
 Intro
 Define the equation of a circle and graph it on a
coordinate plane.
 Standards- 9.7 (power)
 Supplies – slides, whiteboard, note sheets
 Timing: One day for notes, one day for a combined
review of 10.5, 10.6, and 10.7 and a quiz.
 Day 1:
 Essential Questions- slides 2
 Input-slides 3 - 5
 Guided Practice - slides 6 - 9
 Independent Practice – Worksheet