The Circle

1 / 10

# The Circle - PowerPoint PPT Presentation

##### The Circle

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
##### Presentation Transcript

1. Chapter 3 Conics 3.3 The Circle 3.3.1 MATHPOWERTM 12, WESTERN EDITION

2. Developing the Standard Forms of the Equation of a Circle Note: The standard form of the equation of a circle with its centre at the origin (0, 0) is 3.3.2

3. Developing the Standard Forms of the Equation of a Circle This is the of the equation of a circle with the centre at 3.3.3

4. Finding the Equation of a Circle Determine the equation of a circle with centre C(-5, 2) and passing through the point P(-8, 7). From the standard form: (x - h)2 + (y - k)2 = r2 Therefore, the equation of the circle in standard form is 3.3.4

5. Writing the General Form of the Equation of a Circle The general form of the equation is Write the following equation in general form: (x + 5)2 + (y - 2)2 = 34 3.3.5

6. Finding the Centre and the Radius Find the centre and the radius of each circle: 1.x2 + y2 - 8x + 10y - 14 = 0 To find the centre and radius, write the equation in standard form. To do this, you must complete the square: x2 + y2 - 8x + 10y - 14 = 0 The centre is and the radius is 2.3x2 + 3y2 + 6x + 12y + 5 = 0 The centre is and the radius is 3.3.6

7. Using a Graphing Calculator Graph: (x - 3)2 + (y - 4)2 = 16 Your calculator will only graph a function, therefore, you must write the equation in the form y = . Make sure that you use a ZSquare graphing window. You can also use the Draw circle command on your TI-83: Press [2nd][PRGM] 9 and enter the following: 3.3.7

8. Using a Graphing Calculator Using your graphing calculator, graph the following equations: a) x2 + y2 = 16 b) 4x2 + y2 = 16 c) 0.5x2 + y2 = 16 d) Ax2 + y2 = 16, when A = 0 3.3.8

9. Using a Graphing Calculator [cont’d] Using your graphing calculator, graph the following equations: d) x2 + 4y2 = 16 e) x2 + 0.5y2 = 16 f) x2 + Cy2 = 16, when C = 0 3.3.9

10. Assignment Suggested Questions: Pages 141 and 142 A 1-25 odd, 27-32 B 36-45, 49, 50, 51, 54, 56, 58 (graph), 62 3.3.11