In these lessons, we will learn how to find the circumference of a circle, arc length, area of a circle, area of sector, tangent of a circle, inscribed and circumscribed polygons.

Any line segment joining two points on the circle is called a chord. The terms “radius” and “diameter” can also refer to line segments: A radius is any line segment joining a point on the circle and the center of the circle, and a diameter is any chord that passes through the center of the circle.

The distance around a circle is called the circumference of the circle, which is analogous to the perimeter of a polygon. The ratio of the circumference C to the diameter d is the same for all circles and is denoted by the Greek letter π (pi).

This video will help you understand the relationship between the radius diameter and circumference of a circle.

C = πd = 2πr

In this video, you will learn about Central Angles and their relationship to Arcs. You will also learn about Chords and their relationships to Arcs and Central Angles.

This video lesson discusses how to find the length of an arc. First, the arc length theorem is reviewed and explained. An example of find the length of a major arc is modeled. The given information is the measure of the related minor arc and the radius of the circle.

This video shows how to get the area of a circle and how it relates to radius and diameter.

This video shows how to find the area of a sector.

This video provides example problems of determining unknown values using the properties of a tangent line to a circle.

A polygon is circumscribed about a circle if each side of the polygon is tangent to the circle, or equivalently, the circle is inscribed in the polygon.

This video shows how to solve problems involving quadrilaterals inscribed in circles. This video shows that if an inscribed triangle is a right triangle, then the hypotenuse is the diameter. If an inscribed angle has a diameter as one of its sides, then its a right triangle. Tjis video gives a lesson on polygons inscribed in and circumscribed about a circle.

Rotate to landscape screen format on a mobile phone or small tablet to use the **Mathway** widget, a free math problem solver that **answers your questions with step-by-step explanations**.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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