Chapter 10

Question 1

Center

Answer 1

part of a circle that all points are equidistant from

Question 2

Central Angle

Answer 2

angle with vertex in center of circle

Question 3

chord

Answer 3

segment with endpoints on the circle

Question 4

circle

Answer 4

set of all points equidistant from a given point

Question 5

circumference

Answer 5

distance around the circle

Question 6

diameter

Answer 6

chord that passes through center and is made of collinear radii

Question 7

pi

Answer 7

the ration c/d, as an irrational number

Question 8

radius

Answer 8

segment with endpoints at center and on the circle

Question 9

Circle pairs

Answer 9

1. 2 circles are congruent if they have congruent radii

2. all circles are similar

Question 10

Concentric Circles

Answer 10

coplanar circles with same center

Question 11

Inscribed polygon

Answer 11

polygon with vertices on the circle

Question 12

Circumscribed polygon

Answer 12

polygon outside the circle

Question 13

Arc

Answer 13

portion of the circle defined by 2 endpoints

Question 14

Central Angle

Answer 14

angle with vertex in the center of the circle

Question 15

Sum of Central Angles

Answer 15

360 degrees

Question 16

Minor arc

Answer 16

connecting two endpoint that make up less than 180*

Question 17

Major arc

Answer 17

connecting two endpoint s that make up more than 180*

Question 18

Semicircle

Answer 18

arc with endpoints that lie on a diameter, or 180*

Question 19

Congruent Arcs

Answer 19

arcs in same or congruent circles that have the same measure

Question 20

In the same circle or in congruent circles, two minor arcs are congruent if an only if….

Answer 20

their central angles are congruent

Question 21

Adjacent arc

Answer 21

arcs in a circle with exactly one point I common

Question 22

Measure of arc formed by 2 adjacent arcs is the sum of the measure of

Answer 22

the two arcs

Question 23

Arc Length

Answer 23

distance between endpoints along an arc, measured in degrees

Question 24

in the same circle or congruent circles, 2 minor arcs are congruent if and only if their corresponding chords are…

Answer 24

congruent

Question 25

If a diameter or radius of a circle is perpendicular to a chord, then it...

Answer 25

bisects the chord and its arc

Question 26

The perpendicular bisector of a chord is...

Answer 26

the diameter or radius of a circle

Question 27

In the same circle or in congruent circles, 2 chords are congruent if and only if they are _______ from the _______

Answer 27

equidistant, center

Question 28

Inscribed Angle

Answer 28

angle with a vertex on the circle and sides that contain chords of the circle

Question 29

Intercepted Arc

Answer 29

endpoints on the sides of an inscribed angle and lies on the interior of the inscribed angle

Question 30

If an angle is inscribed in a circle, the measure of the circle is ____ of the intercepted arc

Answer 30

1/2

Question 31

If two inscribed angles of a circle intercept the same arc or congruent arcs, the angles are

Answer 31

congruent

Question 32

An inscribed angle of a triangle intercepts a diameter or semicircle only if the angle is a _______ angle

Answer 32

right

Question 33

If a quadrilateral is inscribed in a circle, it's opposite angles are....

Answer 33

supplementary

Question 34

Tangent to a Circle

Answer 34

a line that intersects the circle at exactly one point

Question 35

Common Tangent

Answer 35

line, Ray, or segment that is tangent to 2 circles in the same plane

Question 36

In a plane, a line is tangent to a circle if and only if it is _______ to a radius drawn to point of tangency

Answer 36

perpendicular

Question 37

If two segments from the same exterior point are tangent to a circle, they are....

Answer 37

congruent

Question 38

Secant

Answer 38

line that intersects a circle at 2 points

Question 39

If an angle's vertex is at the center of the circle, it's measure is _____

Answer 39

same as the measure of the arc

Question 40

If an angle's vertex is on the circle, it's measure is

Answer 40

1/2 the measure of it's arc

Question 41

If an angle's vertex is on the interior of the circle, it's measure is.....

Answer 41

1/2 (sum of arc)

Question 42

If an angle's vertex is on the exterior of the circle, it's measure is....

Answer 42

1/2 (difference of arcs)

Question 43

chord segments

Answer 43

two chords that intersect inside a circle, each chord being divided into 2 segments

Question 44

secant segment

Answer 44

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

Question 45

If 2 chords intersect in a circle, their _______ are equal

Answer 45

products

Question 46

external secant segment

Answer 46

secant segment that lies on the outside of the circle with one endpoint on the circle

Question 47

If 2 secants intersect on the outside of the circle, you.....

Answer 47

multiply the outside (external secant segments) by the outside plus the inside (x(x+y)) and those equal each other

Question 48

If a tangent and a secant intersect in the exterior of a circle, the _______ equals the _______

Answer 48

square of tangent, product of secant and ESS

Question 49

"Completing the square" Formula

Answer 49

(b/2)^2

Question 50

Equation of a Circle in Standard Form

Answer 50

(x-h)^2 + (y-k)^2 = r^2