Chapter 10 vocab (Geometry)

Circle

The collection of all points in a plane that are equidistant from a given point (center).

Center of a Circle

The point from which all points that lie on a circle are equidistant.

Radius

A segment in a circle in which one endpoint lies on the circle while the other lies on the center

Diameter

A segment in a circle in which both endpoints lie on the circle, and it passes through the center

Chord

A segment in which both endpoints are on the circle

Secant

A line that intersects a circle at 2 points

Tangent of a circle

A line in a plane of a circle that intersects the circle at exactly 1 point

Point of tangency

The point at which a tangent line/segment/ray intersects a circle

Concentric Circles

Coplanar circles that have a common center

Circumscribed Circles

A circle that contains all the vertices of an inscribed polygon

Inscribed Polygon

An angles whose vertex is center a circle and whose sides are cords of a circle

Interscribed Polygon

A polygon in which all vertices lie on a circle

Subtend

If the endpoint of a chord or arc lie on the lies of an inscribed angle the chord of arc is said to subtend the angle

Common Tangent

A segment or a line that is tangent to 2 or more coplanar circles

Common internal tangent

A common tangent that intersects the segment that joins the center of 2 circles

Common External tangent

A common tangent hat does not intersect the segment that joins the center of 2 circles

Semi circle

An arc with endpoints of a diameter

Central Angle

An angle whose vertex is the center of a circle

Minor Arc

An arc with a measure of less than 180

Major Arc

An arc with a measure of greater than 180

Adjacent Arcs

Arcs of a circle that have only one point in common

Congruent Arcs

Arcs that have the same measure and are of the same circle or of congruent circles

Similar Arcs

Arcs that have the same measure

Congruent Circles

Circle that have the same radius

Tangent Circles

Coplanar circles that intersect at 1 point