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# Circle arcs and sectors

5 videos
2 skills
This tutorial will review some of the basic of circles and then think about lengths of arcs and areas of sectors.

### Language and notation of the circle

VIDEO 11:12 minutes
Formal definition of a circle. Tangent and secant lines. Diameters and radii. major and minor arcs

### Circles: radius, diameter, circumference and Pi

VIDEO 11:05 minutes
A circle is at the foundation of geometry and how its parts relate to each other is both completely logical and a wonder.

### Length of an arc that subtends a central angle

VIDEO 4:58 minutes

### Finding central angle measure given arc length

VIDEO 2:18 minutes

### Circles and arcs

PRACTICE PROBLEMS
Relate the length of an arc to the circumference of a whole circle.

### Area of a sector given a central angle

VIDEO 2:26 minutes

### Areas of circles and sectors

PRACTICE PROBLEMS
Relate the area of a sector to the area of a whole circle.