Upcoming SlideShare
×

# Circles

• 5,232 views

More in: Education
• Comment goes here.
Are you sure you want to
Are you sure you want to

Total Views
5,232
On Slideshare
0
From Embeds
0
Number of Embeds
0

Shares
0
1
Likes
14

No embeds

### Report content

No notes for slide

### Transcript

• 1. CIRCLES
• 2. Definitions
pg 293
A circle is the set of all points in a plane equidistant from a given point, called the center.
B
r
O
r
r
C
A
• 3. Definitions
pg 293
A secant of a circle is a line that intersects the circle in two points.
A chord of a circle is a segment whose endpoints lie on the circle.
• In the figure, AB is a chord.
• 4. Thus, every secant contains a chord.
B
A
• 5. Definitions
pg 293
A diameter of a circle is a chord containing the center. It is the longest chord.
A radius of a circle is a segment from the center to a point on the circle.
O
A
B
Diameter = AB
diameter
What is the relationship between a radius and a diameter?
• 6. Identify if the following is a radius, diameter, or chord.
BC
EI
FJ
GD
GF
IF
FH
DA
MK
FM
• Identify if the following is a radius, diameter, or chord.
GF
EG
GN
BM
GL
KL
GK
EK
GB
• Identify if the following is a radius, diameter, or chord.
JH
TX
CL
GD
EH
MN
VC
NL
KP
CQ
• TANGENTS LINES TO CIRCLES
• 34. pg 294
The interior of a circle is the set of all points of the plane whose distance from the center is less than the radius. (inside)
Theexterior of a circle is the set of all points of the plane whose distance from the center is greater than the radius. (outside)
O
Exterior
Interior
• 35. pg 294
A tangent line to a circle is a line in the plane of the circle that intersects the circle in exactly one point.
The point where a circle and a tangent intersect is the point of tangency.
• 36. Tangents and Secants
Tangents and secants are LINES.
A tangent line intersects the circle at exactly ONE point.
A secant line intersects the circle at exactly TWO points.
• 37. A little extra information
• The word tangent comes from the Latin word meaning to touch
• 38. The word secant comes from the Latin word meaning to cut.