# 12-5 Circles in the Coordinate Plane

## Presentation on theme: "12-5 Circles in the Coordinate Plane"— Presentation transcript:

12-5 Circles in the Coordinate Plane
To write an equation of a circle. To find the center and radius of a circle.

12-5 Quiz The following questions are to help you decide how well you understood today’s lesson. Be sure to ask if you miss one and don’t understand why. Record the number you get right on your portfolio sheet!

(x – 7)2 + (y + 3)2 = 16 (x – 7)2 + (y – 3)2 = 4
Countdown 90 (x – 7)2 + (y + 3)2 = 16 (x – 7)2 + (y – 3)2 = 4 (x + 7)2 + (y – 3)2 = 16 (x + 3)2 + (y – 7)2 = 16 Non-Response Grid

2. Write the standard equation for the circle
2. . Write the standard equation for the circle. center (–6, 8), that passes through (0, 0) Countdown 90 Non-Response Grid

center (–2, –3); r = 7 center (–2, –3); r = 49 center (– 2, 3); r = 7
Countdown 90 center (–2, –3); r = 7 center (–2, –3); r = 49 center (– 2, 3); r = 7 center (2, –3); r = 7 Non-Response Grid

4. A low-wattage radio station can be heard only within a certain distance from the station. On the graph below, the circular region represents that part of the city where the station can be heard, and the center of the circle represents the location of the station. Which equation represents the boundary for the region where the station can be heard? Countdown 90 Non-Response Grid

5. Write the standard equation of the circle in the graph.
Countdown 90 (x – 3)2 + (y + 2)2 = 9 (x + 3)2 + (y – 2)2 = 9 (x – 3)2 + (y + 2)2 = 3 (x + 3)2 + (y – 2)2 = 3 Non-Response Grid

12-5 p.801-802 #8-52 even ASSIGNMENT:
Be sure to RATE your understanding of the lesson after you finish it AND give me one complete sentence as to why you rated yourself that way then summarize what the lesson was about in a couple of complete sentences.