Circles: Area and Circumference. Definitions Circumference: Distance around the outside of a circle Area: How many squares it takes to cover a circle.

Slides:

Advertisements

Similar presentations

Radius The distance from the center of a circle to any point on the circle. M A point on the circle Center.

Advertisements

M5G2 – Students will understand the relationship of the circumference of a circle, its diameter, and pi (pi ≈ 3.14)

By Maria Bocanegra. The distance around a closed curved circle. WHAT IS CIRCUMFERENCE?

Definition: A circle is the set of all points on a plane that is a fixed distance from the center.

Perimeter Rectangles, Squares, and Triangles Perimeter Measures the distance around the edge of any flat object. To find the perimeter of any figure,

Radius, Diameter, and Circumference of a Circle Lesson 7 (3 rd 6 Weeks) TEKS 6.6C.

1.You will explain the definition of a circle, radius, chord, diameter, circumference and arc. 2.You will name and label the terms of a circle. 3.You will.

The Area and Componants of Circles. Free powerpoint template: 2 Circles Vocabulary pi or π (pi) Π is a mathematical constant with.

Circles & Circumference 8 th Grade Pre-Algebra Circles & Circumference PPT Molly Thompson.

1. 2 Circle A circle is the set of all points that are the same distance from a given point called the center.

The outside of the circle is called circumference The circumference is the distance around the circle.

GEOMETRYGEOMETRY Circle Terminology. Student Expectation 6 th Grade: 6.3.6C Describe the relationship between radius, diameter, and circumference of a.

  investigate the relationship between the diameter and circumference of a circle.

Circle Formulas Vocabulary: Circumference Radius Diameter Pi.

Review Multiplying decimals: 3.2 x 5.12 Multiplying fractions and whole numbers: 5 x 2/3.

Chapter 10 Lesson 1: Circles and Circumference Objective: Learn to find the circumference of circles.

Math Circumference of Circles & Area of Circles. Vocabulary A circle is the set of all points in a plane that are the same distance from a given point,

Circles and Circumference Lesson 9-5. Vocabulary A circle is a plane figure that consists of a set of points that are equidistant from a given point called.

Circles and Circumference. Vocabulary A circle is a plane figure that consists of a set of points that are equidistant from a given point called the center.

Circumference & Pi    3.14.

8-1C The Circumference of a Circle What is circumference? What is pi? What is the symbol for pi? What are the formulas for the circumference of a circle?

Circle Geometry.

Circumference and Area: Circles

Warm-Up  Multiply.  1.89 x 97  x 76  x 34  4.38 x 28.

Area and Circumference of a Circle 2 Definitions A circle is the set of all points in a plane that are the same distance from a fixed point called the.

8.7 Circumference and Area of Circles. Definition  A circle is the set of all points in a plane that are the same distance from a given point, called.

UNIT 9: GEOMETRY – 6 TH GRADE LESSON 5: AREA OF A CIRCLE.

6.12 Solve problems involving the circumference &/or area of a circle when given the diameter or radius. Derive approximations for pi(π) from measurements.

LESSON 7.6 AREA AND CIRCUMFERENCE OF CIRCLES OBJECTIVE: To use formulas for the circumference and area of circles.

Circumference Wilfredo Rodriguez Multimedia Project #4.

Circumference and Diameter 1/31/2006. Circumference A circle is a shape with all points the same distance from the center. It is named by the center.

1 of 84 SHAPE AND SPACE Circles. 2 of 84 The circumference of a circle Use π = 3.14 to find the circumference of this circle. C = πd 8 cm = 3.14 × 8 =

Warm-Up Find the area: Circumference and Area Circles.

The Circle. The language of circles Circumference: The distance round the circle Circumference: The distance round the circle Diameter: the distance from.

Circumference Lesson #33. What is Circumference? The distance around the outside of a circle is called the circumference (essentially, it is the perimeter.

Revision Formulae: Diameter = 2 x Radius Area of Circle = πr 2 Circumference of circle = 2πr = πd π = 3.14 approximately.

SPI I CAN identify parts of a circle. I CAN find the circumference and area of a circle.

Hannah D..  Radius is half the way across the circle  Diameter is the whole way across the circle.

Geometry – Circles.  Circles are shapes made up of all points in a plane that are the same distance from a point called the center.  Look at this example.

Circles and Circumference. Vocabulary A ________is a plane figure that consists of a set of points that are equidistant from a given point called the.

Circles. diameter Circumference radius Circumference- the distance around the circle. About 3X the diameter.

Circles By Freddie And Liam.

9-1 Exploring Circles Objectives: To identify and use parts of circles. To solve problems involving the circumference of a circle.

Introduction & Installation. Circles A circle is a shape with all points the same distance from the center. A circle is named by the center. The circle.

CIRCLES CIRCUMFERENCE & AREA. CIRCUMFERENCE C = ΠdorC = 2Πr 12cm.

By: Kay McInnis. Diameter DIAMETER is the distance across a circle passing through the center point.

+ Bell Work Solve 25 ⅚ -18 ⅜ 5 ⅛ + 7 ⅘. + Bell Work Answer 25 ⅚ -18 ⅜ 25 20/24 – 18 9/ /24 5 ⅛ + 7 ⅘ 5 5/ / /40.

How do you find the circumference of a circle? For Example A circle has a radius of 8 centimeters. What is the circumference of the circle?

By Renikki Alexander IDT 7062 Let’s Listen to the Circle Song "πr 2 sounds like area to me and when I need circumference I'll use πd."

Circles Circumference and Area 6 th Grade Math LaVergne Middle School.

Circumference & Surface Area Today’s lesson will cover…  finding circumference and surface area of circles  using formulas to solve problems involving.

The midpoint of a circle is centre The line drawn from the centre to the circumference is … radius.

Circles: Circumference What do we call the measure of the perimeter of a circle or the distance around a circle? circumference.

Circles Shape and Space. The value of π For any circle the circumference is always just over three times bigger than the radius. The exact number is called.

Objective: Solve equations using area circumference, diameter, and radius.

Do Now:. Circumference What is circumference? Circumference is the distance around a circle.

Introduction & Installation. Circles A circle is a shape with all points the same distance from the center. A circle is named by the center. The circle.

CIRCLES AND CIRCUMFERENCE. CONTINUATION OF PI DAY In every circle, the ratio of the circumference to the diameter is equal to …… The Greek letter.

Geometry: Circles and Circumference

Circles Circles are EVERYWHERE..

Circles: Circumference & Area

Circles: Circumference & Area

Spiral TAKS Review #2 6 MINUTES.

Circumference and Area: Circles

Geometry: Circles and Circumference

Presentation transcript:

Circles: Area and Circumference

Definitions Circumference: Distance around the outside of a circle Area: How many squares it takes to cover a circle

Definitions Radius: A line segment that goes from the center of the circle to the edge of the circle. radius diameter Diameter: Goes from edge to edge through the middle. Diameter = 2 times radius or d = 2r Radius = ½ times diameter or r = d/2

Definitions Pi: Measure of the distance around the circle / (divided by) the diameter or distance across the circle and you ALWAYS get We round this to 3.14 and call it Pi or use the symbol for pi which is π.

Definitions Circumference: If you know the diameter of a circle you can find the circumference by using this formula: C = pi · d or C = πd But what if you only know the radius? C = pi · 2 · r or C = 2πr

Definitions Area: The number of squares it takes to cover a circle A = pi · r · r or A = πr² But what if you only know the radius? Divide the diameter in half to get the radius and then use the formula.

Examples Example 1: The radius of a circle is 2 inches. What is the diameter?  d = 2 · r  d = 2 · (2 in)  d = 4 in

Examples Example 2: The diameter of a circle is 3 centimeters. What is the circumference?  C = π· d  C = 3.14 · 3 cm  C = 9.42 cm

Examples Example 3: The radius of a circle is 2 inches. What is the circumference?  d = 2 · r  d = 2 · (2 in)  d = 4 in  C = π · d  C = 3.14 · (4 in)  C = in

Summary The number π is the ratio of the circumference of a circle to the diameter. (π = C/r) The value of π is approximately The diameter of a circle is twice the radius. Given the diameter or radius of a circle, we can find the circumference. The formula for diameter is d = 2 · r The formula for circumference is C = π · d