Central Angles and Arcs

1
Central Angles and Arcs

• An angle whose vertex is on the center of the
  circle is a CENTRAL ANGLE. If it measures less
  than 180, it is a minor arc. If it measures
  180, the arc is a semicircle.

2
B
AB is a minor arc
B
ltAPB is a central angle
P
A
A
ACB is a major arc. Major arcs and
semicircles are denoted w/ 3 letters.
B
C
P
A
3
Measuring an arc

• The measure of a minor arc is defined to be the
  measure of its central angle.

A
So, if mltACB is 110, Then mAB 110
C
B
4
Arc Addition Postulate

• The measure of an arc formed by two adjacent arcs
  is the sum of the measures of the two arcs.

5
Theorem 10.4

• In the same circle, or congruent circles, two
  arcs are congruent if and only if their central
  angles are congruent.

6
D
A
Name a central lt of circle P. Name the minor
arcs of circle Q. Which arcs are semicircles?
40
B
P
C
E
40
F
Q
G
7
D
A
What is the major arc associated with ltAPB? What
is mEF? What is mACB? Name two adjacent minor
arcs in circle Q. Write arc postulate.
40
B
P
C
E
40
F
Q
G
8
A square is circumscribed about a circle. What is
the ratio of the area of the circle to the area
of the square?
9
Character Counts
Persevere keep on trying.
Always do your best.
Responsibility
Think before You act.
10
Meeting the Needs

• List the products and features, and how each
  addresses a specific need or solves a specific
  problem
• This section may require multiple slides

11
Cost Analysis

• Point out financial benefits to the customer
• Compare cost-benefits between you and your
  competitors

12
Our Strengths
13
Key Benefits

• Summarize the key benefits provided by the
  product, service, or idea being promoted

14
Next Steps

• Specify the actions required of your audience