11.3 Sector Area and Arc Length (Part 1)

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Presentation transcript:

11.3 Sector Area and Arc Length (Part 1) Geometry

Reminder: Circumference Circumference is the distance around a circle (Perimeter) C=2лr or C=лd

Reminder: Measuring An Angle We measure an arc in degrees We can find the length of an arc in linear units as well (meters, feet, inches, etc.) Arc Length Formula arc length 2𝜋𝑟 = 𝑛 360

Note: mAB = the degree measure of the arc Length of AB= how long it is in cm, in, ft., etc.

Examples

11.3 Sector Area and Arc Length (Part 2) Geometry

Reminder: Area Area of a circle A = 𝜋 𝑟 2

Sector of a Circle Sector – region bounded by two radii and their intercepted arc Piece of pizza

Area of A Sector To find the area of a sector of a circle (area of a piece of pizza) area of sector 𝜋 𝑟 2 = 𝑛 360

Examples