11.2.1 Inscribed Angles Flashcards
1
Q
inscribed angle
A
an angle whose vertex is on a circle and whose sides contain chords of the circle
2
Q
intercepted arc
A
consists of endpoints that lie on the sides of an inscribed angle and all the points of the circle between
them
3
Q
subtends
A
a chord or arc subtends an angle if its endpoints lie on the sides of the angle
4
Q
Inscribed Angle Theorem
A
The measure of an inscribed angle is half the measure of its intercepted arc.
M∠ABC = 1/2M(arcAC)
5
Q
Corollary
A
If inscribed angles of a circle intercept the same arc or are subtended by the same chord or arc, then the angles
are congruent.
6
Q
Theorem
A
An inscribed angle subtends a semicircle if and only if the angle is a right angle.
7
Q
Theorem
A
If a quadrilateral is inscribed in a circle, then its opposite angles are supplementary.
