central angle - an angle whose vertex is at the center of the circle
chord - a segment joining two points on a circle
circle - the set of all points in a plane that are a given distance from a given point in the plane (that point is called the circle's center.)
concentric - having the same center
cyclic quadrilateral - a quadrilateral inscribed in a circle, that is one whose vertices are all on the circle with the quadrilateral contained within the circle.
inscribed angle - an angle whose vertex is on a circle and who sides are determined by two chords
length (of an arc) - how long the arc is; this is found as the fraction of the circumference taken up by the arc times the circumference of the circle
major arc - an arc that has a measure greater than 180 degrees; three points must be used to denote the major arc as two points denotes the shorter path between them which is the minor arc.
measure (of an arc) - in degrees, the measure of the central angle that describes the arc
minor arc - an arc whose measure is less than 180 degrees
secant - a line that intersects a circle at exactly two points (This continues outside the circle as well as including a chord.)
tangent (of a circle) - A line that intersects a circle at exactly one point. The tangent is perpendicular to the radius that goes to the point of tangency.
Important fact:
All circles are similar.
chord - a segment joining two points on a circle
circle - the set of all points in a plane that are a given distance from a given point in the plane (that point is called the circle's center.)
concentric - having the same center
cyclic quadrilateral - a quadrilateral inscribed in a circle, that is one whose vertices are all on the circle with the quadrilateral contained within the circle.
inscribed angle - an angle whose vertex is on a circle and who sides are determined by two chords
length (of an arc) - how long the arc is; this is found as the fraction of the circumference taken up by the arc times the circumference of the circle
major arc - an arc that has a measure greater than 180 degrees; three points must be used to denote the major arc as two points denotes the shorter path between them which is the minor arc.
measure (of an arc) - in degrees, the measure of the central angle that describes the arc
minor arc - an arc whose measure is less than 180 degrees
secant - a line that intersects a circle at exactly two points (This continues outside the circle as well as including a chord.)
tangent (of a circle) - A line that intersects a circle at exactly one point. The tangent is perpendicular to the radius that goes to the point of tangency.
Important fact:
All circles are similar.