math ch10 rules

dana alkadhi 10c

10.6

10.3

10.1

radius

10.2

sum of central angles

if a diameter/radius of a circle is perpendicular to a chord, then it bisects the chord & its arc

10.4

secant

10.5

in the same circle/congruent circles, 2 chords are congruent only if they are equidistant fro the center

segment w/endpoints at the center & on the circle

chord

segment w/endpoints on the circle

diameter

chord that passes through the center & is made up of collinear radii

r=d/2

d=2r

2 circle are congruent only if they have congruent radii

all circle are similar

centric circles

coplanar circles that have the same center

sum of the measure of the central angles of a circle with no interior points in common is 360

minor arc

<180

major arc

180

semicircle

=180

arc length

l=x/360 x 2 x 3.14 x r

perpendicular bisector of a chord is a diameter/ radius of a circle

inscribed angle

vertex on a circle & its sides contain chords of the circle

intercepted arc

endpoints on the sides of an inscribed angle & lies in its interior

tangent

line in the same plane as a circle that intersects the circle in exactly 1 point

point of tangency

common tangent

line/ray/segment that's tangent to 2 circles in the same plane

line that intersects a circle in exactly 2 point

10.8

10.7

secant segment

segment of a secant line that has exactly one endpoint on the circle

external secant segment

secant segment that lies in the exterior of the circle