Basic Geometry Unit 10.7 – Circles: Circumference and Area
Story Time…Again!
Circles <ul><li>A  circle  is the set of all points in a plane that are a same distance from a given point in the plane. <...
Circles <ul><li>A distance from the center to any point on the circle is called the  radius  ( r ). </li></ul><ul><li>The ...
<ul><li>The  circumference  of a circle is the distance around the circle. </li></ul><ul><li>The ratio of the circumferenc...
Formulas <ul><li>Circumference of a Circle :  If a circle has a radius of  r  units, then  C   = 2 π r . </li></ul><ul><li...
Find the area and circumference of each circle.  Round to the nearest tenth. 5 ½ in. 15.6 m
Questions? <ul><li>Homework </li></ul><ul><ul><li>10.7 WKS </li></ul></ul>
Upcoming SlideShare
Loading in …5
×

10.7 notes

1,094 views

Published on

Part of the geometry unit

Published in: Education
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,094
On SlideShare
0
From Embeds
0
Number of Embeds
4
Actions
Shares
0
Downloads
24
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

10.7 notes

  1. 1. Basic Geometry Unit 10.7 – Circles: Circumference and Area
  2. 2. Story Time…Again!
  3. 3. Circles <ul><li>A circle is the set of all points in a plane that are a same distance from a given point in the plane. </li></ul><ul><li>The given point is called the center . </li></ul>
  4. 4. Circles <ul><li>A distance from the center to any point on the circle is called the radius ( r ). </li></ul><ul><li>The distance across the circle through its center is its diameter ( d ). </li></ul>r d
  5. 5. <ul><li>The circumference of a circle is the distance around the circle. </li></ul><ul><li>The ratio of the circumference of a circle to its diameter is the irrational number called π ( pi ). We often use 3.14 or as approximations. </li></ul>
  6. 6. Formulas <ul><li>Circumference of a Circle : If a circle has a radius of r units, then C = 2 π r . </li></ul><ul><li>Area of a Circle : If a circle has a radius of r units, then the area A is A = π r 2 square units. </li></ul>
  7. 7. Find the area and circumference of each circle. Round to the nearest tenth. 5 ½ in. 15.6 m
  8. 8. Questions? <ul><li>Homework </li></ul><ul><ul><li>10.7 WKS </li></ul></ul>

×