Unit 14 - Circles

Question 1

Definition of Congruent Circles

Answer 1

Circles with different centers but same radii

Question 2

Definition of Central Angle

Answer 2

1. Angle with a vertex AT THE CENTER OF CIRCLE
   2.

Question 3

Definition of Concentric Circles

Answer 3

Circles with same centers but different radii

Question 4

Definition of Semi - Circle

Answer 4

180 Degree Arc

Question 5

What is a list of theorems/techniques that can be used to solve a diagram?

Answer 5

1. All Radii are Congruent
2. Measure of CA = Measure of Intercepted Arc
3. 2 Minor Arcs are ≅ if their CAs are ≅
4. 2 CAs are ≅ if their Minor Arcs are ≅
5. Inscribed Angle Thm - Measure of inscribed angle = 1/2 intercepted arc
6. Thales Thm - 2 Inscribed Angles w/ same/congruent arcs are ≅

Question 6

When are Minor Arcs congruent? (3)

Answer 6

1. In Same Circle/Congruent Circles
2. Two minor arcs are congruent
3. If and only if Central Angles are Congruent

Question 7

Formula for Arc Length

Answer 7

ℒ /2πr = X/360

Question 8

Formula for Arc Area

Answer 8

As/πr² = X/360

Question 9

Definition of Inscribed Angle (2)

Answer 9

1. Vertex on Circle Edge
2. Sides are Chords

Question 10

Definition of Inscribed Angle Theorem (2)

Answer 10

Measure of inscribed angle = 1/2 intercepted arc

Question 11

Definition of Thales’ Thereom

Answer 11

2 Inscribed Angles w/ same/congruent arcs are ≅