inscribed angles and central angles Flashcards
What is an inscribed angle?
An inscribed angle is an angle where the vertex lies on one of the points on a circle
What is a central angle?
A central angle is an angle where the vertex lies on the center of the circle
How do you find the measure of a minor arc?
The measure of a minor arc is equal to the measure of its corresponding central angle
What is a tangent?
A line or part of a line that intersects a circle in one point (a point on a circle)
What is a chord?
Segment whose endpoints are on a circle
What is theorem 12-4?
Within a circle or in congruent circles, congruent central angles have congruent arcs
What is theorem 12-5?
Within a circle or in congruent circles, congruent central angles have congruent chords
What is theorem 12-6?
Within a circle or in congruent circles, congruent chords have congruent arcs
What is theorem 12-7?
Within a circle or in congruent circles, chords equidistant from the center or centers are congruent
What is theorem 12-8?
In a circle, if a diameter is perpendicular to a chord, then it bisects the chord and its arc
What is theorem 12-9?
In a circle, if the diameter bisects a chord (that is not a diameter), then it is perpendicular to the chord
What is theorem 12-10?
In a circle, the perpendicular bisector of a chord contains the center of the circle
What is theorem 12-11?
The measure of an inscribed angle is half the measure of its intercepted arc
What is corollary 1 of theorem 12-11?
If two inscribed angles intercept the same arc, the angles are congruent
What is corollary 2 of theorem 12-11?
An angle that is inscribed in a semicircle is always a right angle
