Objectives: Students will use a ruler to measure diameters of circles and then find area and circumference of circles. M11.C.1.

Slides:

Advertisements

Similar presentations

C=π d C=2πr r=½d d=rx2 A=πr² The diameter is the longest chord. The ratio of the circumference is always …. π is a Greek letter. π can also.

Advertisements

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

Lesson 16: The Most Famous Ratio of All

Using Formulas in Geometry

Using Formulas in Geometry

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

Using Formulas in Geometry

Area and Circumference of Circles

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

Lesson 8.1: Perimeter and Circumference

Splash Screen. Lesson Menu Five-Minute Check (over Lesson 11–2) Main Idea and Vocabulary Key Concept: Circumference of a Circle Example 1:Real-World Example:

Area of a Circle. The area A of a circle equals the product of π and the square of its radius r. When finding the area of a circle, you have to use the.

Circle Formulas Vocabulary: Circumference Radius Diameter Pi.

Target Apply formulas for perimeter, area, and circumference.

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,

Pi Video. Vocabulary 1. Circle – a set of points equidistant from a given point. 2. Center- a given point from which all points are the same distance.

Lesson 1 MI/Vocab circle center radius diameter circumference pi Find the circumference and area of circles.

Splash Screen. Lesson Menu Five-Minute Check (over Lesson 11–6) Then/Now New Vocabulary Key Concept: Circumference of a Circle Example 1: Find the Circumference.

Circumference and Area: Circles

Lesson 10-7 Pages Circumference and Area: Circles.

11-3 Areas of Circles and Sectors

10/14/ : Circumference and Area of Circles 5.3: Circumferences and Areas of Circles Expectation: G1.6.1: Solve multistep problems involving circumference.

Bell Work: Write 2 formulas for the circumference of a circle.

Objective Apply formulas for perimeter, area, and circumference.

Objective Apply formulas for perimeter, area, and circumference.

Lesson 7-2 Circumference and Area of Circles. Definitions Circle - A set of points in a plane that are the same distance away from a given point in the.

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

Warm up: Solve for x 18 ◦ 1.) x 124 ◦ 70 ◦ x 2.) 3.) x 260 ◦ 20 ◦ 110 ◦ x 4.)

Warm up: Solve for x 1.) 2.) 4.) 3.) 124◦ 70◦ x 18◦ x 260◦ x 20◦ 110◦

Do Now: Solve 5 + 2[(92 – 4) + (23 + 1)] Solve and graph x + 11>25

Note 2: Perimeter The perimeter is the distance around the outside of a shape. Start at one corner and work around the shape calculating any missing sides.

Chapter 4 L4-5 Notes: Perimeter. Vocabulary The distance around any closed figure is called its perimeter. P for “Plus” all Sides.

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 =

Splash Screen Example 9-2b Objective Find the circumference of circles.

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

Ch 11.6 What is the area of a square with an apothem length of 14 in? Round to the nearest tenth if necessary. What is the area of a regular hexagon with.

Chapter 1.7 Notes: Find Perimeter, Circumference, and Area

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.

Circumference & Arc Length of Circles. 2 Types of Answers Rounded Put mode on classic Type the Pi button on your calculator Round Exact Put mode on mathprint.

Geometry Warm Up CIRCLES AND ARCS Objective: To find the circumference and arc length.

Circumference and Area of Circles Math 7. Vocabulary circle centerA circle is a set of points in a plane that are the same distance from a given point,

Warm Up Evaluate. Round to the nearest hundredth

The distance around (or perimeter of) a circle is called the _______.

Warm up: Solve for x 18 ◦ 1.) x 124 ◦ 70 ◦ x 2.) 3.) x 260 ◦ 20 ◦ 110 ◦ x 4.)

Finding Perimeter and Area Review. Perimeter The distance around the outside of an object. 10 feet 8 feet 10 feet Perimeter = = 36 feet.

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

Circumference The distance around a circle or Find the circumference to the nearest tenth

Find the distance between the points below (9, 0) and (5,2) Find the length of the hypotenuse if the length of the legs are 4 and 2.

Geometry Unit: Chapter 8 Quiz Review Lessons 1-4.

EXAMPLE 1 Use the formula for circumference Find the indicated measures. Write circumference formula. Substitute 9 for r. Simplify. Use a calculator.

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

Circles. Parts of a Circle Center The diameter is the distance across the circle through the center The radius is the distance to the center point.

Holt Geometry 1-5 Using Formulas in Geometry Warm Up Evaluate. Round to the nearest hundredth () 6. (3) 2.

Holt McDougal Geometry 1-5 Using Formulas in Geometry 1-5 Using Formulas in Geometry Holt Geometry Warm Up Warm Up Lesson Presentation Lesson Presentation.

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

Opening Activity 1. Find the circumference of a circle with a diameter of 8 ft. Round to the nearest tenth. C= 3.14(8)= 25.1 ft 2. Find the circumference.

Circles and Arcs. General Vocabulary: CIRCLE: the set of all points equidistant from a given point called the CENTER RADIUS: a segment that has one point.

Circles: Circumference & Area

11.1 Circumference and Arc Length 11.2 Areas of Circles and Sectors

Circles: Circumference & Area

Circumference Definition: The distance around a circle. It’s a special word for perimeter. Picture:

Objective Apply formulas for perimeter, area, and circumference.

Using Formulas in Geometry

Objective Apply formulas for perimeter, area, and circumference.

Perimeter and Circumference

Happy Friday!!! Please take out some paper to take notes on today lesson. Be ready to begin class when the bell rings.

Presentation transcript:

Objectives: Students will use a ruler to measure diameters of circles and then find area and circumference of circles. M11.C.1

 On your paper, label each Vocabulary word: -circle -center -diameter -radius -semi-circle -major arc -minor arc

 The circumference of a circle is the distance around the circle. The number pi (π) is the ratio of the circumference of a circle to its diameter.  In your own words, what is another word for circumference? Think about the distance around other shapes such as a triangle or quadrilateral.

 The circumference of a circle is π times the diameter.  C = πd or C =2πr  Why are both formulas above correct when finding the circumference? *Circumference is noted using single units. Ex: inches, feet, etc.

 The area of a circle is the number of square units the figure encloses.  The area of a circle is π times the radius squared.  A = πr² **Area in noted using squared units. Ex: inches squared, feet squared, etc

 Circle G has a radius of 14 cm. Find the circumference of circle G in terms of π. Then find the circumference to the nearest tenth.

 Find the area of circle B in terms of π. Then find the area to the nearest tenth. B 8.4 in

 Using a ruler, measure the diameter of your 5 circular items and record them in the chart provided.  Continue to fill in the chart by finding the radius, area, and circumference of each circle.  Once your chart is complete, give it to your partner along with the circular items so that he/she can check your measurements and calculations.  With your partner, answer the analysis questions.

 Circles that lie in the same plane and have the same center are concentric circles.

 A circular swimming pool with a 16 foot diameter will be enclosed in a circular fence 4 feet from the pool. What length of fencing material is needed? Round to the nearest whole number.

 Brainstorming with your partner, make a list of at least five jobs/careers that would require you to find the area or circumference of a circle. What companies would hire these types of workers?  Write two paragraphs incorporating the careers and jobs that would require finding area and circumference. Would you be interested in one of those jobs in the future?  You will share your ideas with the class.