Theorem 12-12
The measure of an angle formed by a tangent and a chord is half the measure of the intercepted arc. (p. 783)
Theorem 12-13
The measure of an angle formed by two lines that intersect inside a circle is half the sum of the measures of the intercepted arcs. (p. 790)
Theorem 12-14
The measure of an angle formed by two lines that intersect outside a circle is half the difference of the measures of the intercepted arcs. (p. 790)
Theorem 12-15
For a given point and circle, the product of the lengths of the two segments from the point to the circle is constant along any line through the point and circle.
(p. 793)
Theorem 12-16
An equation of a circle with center (h, k) and radius r is
Constructions
Construction 1
Congruent Segments
Construct a segment congruent to a given segment. (p. 43)
Construction 2
Congruent Angles
Construct an angle congruent to a given angle. (p. 44)
Construction 3
Perpendicular Bisector
Construct the perpendicular bisector of a segment. (p. 45)
Construction 4
Angle Bisector
Construct the bisector of an angle. (p. 45)
Construction 5
Parallel Through a Point Not on a Line
Construct the line parallel to a given line and through a given point that is not on the line. (p. 182)
Construction 6
Quadrilateral With Parallel Sides
Construct a quadrilateral with one pair of parallel sides of lengths a and b. (p. 183)
Construction 7
Perpendicular Through a Point on a Line
Construct the perpendicular to a given line at a given point on the line. (p. 184)
Construction 8
Perpendicular Through a Point Not on a Line
Construct the perpendicular to a given line through a given point not on the line. (p. 185)