Download presentation

1
**Lesson 8-1: Circle Terminology**

2
**Lesson 8-1: Circle Terminology**

Circle Definition Circle : The set of points coplanar points equidistant from a given point. The given point is called the CENTER of the circle. The distance from the center to the circle is called the RADIUS. Center Radius Lesson 8-1: Circle Terminology

3
**Lesson 8-1: Circle Terminology**

Definitions Chord : The segment whose endpoints lie on the circle. Diameter : A chord that contains the center of the circle. Tangent : A line in the plane of the circle that intersects the circle in exactly one point. Tangent Point of Tangency : Chord The point where the tangent line intersects the circle. Diameter Secant : A line that contains a chord. Secant Lesson 8-1: Circle Terminology

4
**Lesson 8-1: Circle Terminology**

Example: In the following figure identify the chords, radii, and diameters. Chords: O D A B F C E Radii: Diameter: Lesson 8-1: Circle Terminology

5
**Lesson 8-1: Circle Terminology**

Definitions Congruent Circles : Circles that have congruent radii. 2 2 Concentric circles : Circles that lie in the same plane and have the same center. Lesson 8-1: Circle Terminology

6
**Lesson 8-1: Circle Terminology**

Polygons Inscribed Polygon: A polygon inside the circle whose vertices lie on the circle. Circumscribed Polygon : A polygon whose sides are tangent to a circle. Lesson 8-1: Circle Terminology

7
**Lesson 8-1: Circle Terminology**

ARCS Arcs : The part or portion on the circle from some point B to C is called an arc. A B C Example: B Semicircle: An arc that is equal to 180°. O A Example: C Lesson 8-1: Circle Terminology

8
**Lesson 8-1: Circle Terminology**

Minor Arc & Major Arc Minor Arc : A minor arc is an arc that is less than 180° A minor arc is named using its endpoints with an “arc” above. A Example: Major Arc: A major arc is an arc that is greater than 180°. B B O A major arc is named using its endpoints along with another point on the arc (in order). A Example: C Lesson 8-1: Circle Terminology

9
**Lesson 8-1: Circle Terminology**

Example: ARCS Identify a minor arc, a major arc, and a semicircle, given that is a diameter. Minor Arc: A C D E F Major Arc: Semicircle: Lesson 8-1: Circle Terminology

10
**Formulas Lesson 8-2 Circumference Arc Length Area Sector**

Lesson 8-2: Formulas

11
Central Angle A central angle is an angle whose vertex is at the center of the circle. The arc measure is written as The measure of a minor arc is the measure of its central angle. The measure of a major arc is 360 minus the measure of its central angle. Lesson 8-2: Formulas

12
**CIRCUMFERENCE: Circumference is the distance around the circle.**

Formula: Or where Example: Find the circumference of the following circle. 3 cm cm Lesson 8-2: Formulas

13
**Arc Length Arc length is the distance around an arc. Formula:**

The circumference multiplied by the ratio of the center angle and 360°. Example: Arc Length 2 cm 72 B C A Lesson 8-2: Formulas

14
Area of a Circle Area of a circle is the number of unit squares that can fit into a circle. Formula: Example: Find the area of the following circle. 3 cm Lesson 8-2: Formulas

15
Area of a Sector Area of a sector is the area of a section of the circle. Formula: The area multiplied by the ratio of the center angle and 360° Example: Sector 65° Lesson 8-2: Formulas

Similar presentations

© 2022 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google