FW 3.2: Area of a Circle Learning Target: I will find the area of a circle by estimating and squaring a circle. HW: Complete Inv. 3.2 pkt p. 6 and CORRECT.

Slides:

Advertisements

Similar presentations

Problem 7.1 The Pizzeria sells small, medium, and large pizzas. A small is 9 inches in diameter, a medium is 12 inches in diameter, and a large is 15.

Advertisements

Diameter  Any line segment that passes through the center of the circle and has endpoints on the circle.

TODAY IN GEOMETRY…  Warm up: Writing equations of a circle  Learning Target : 11.4 You will find the arc length and circumferences of circles  Independent.

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

Perimeter and Area. Common Formulas for Perimeter and Area Square Rectangle s l s w A = lw P = 4sP = 2l + 2w Perimeter and Area of Rectangle.

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.

CIRCUMFERENCE OF A CIRCLE LEARNING TARGET 4: I CAN SOLVE PROBLEMS USING AREA AND CIRCUMFERENCE OF A CIRCLE.

Circle Formulas Vocabulary: Circumference Radius Diameter Pi.

Circumference & Area of Circles Unit 5-3. Circumference Formula for Circumference: ** r is the radius ** ** 2r = d. d is the diameter. ** **Circumference.

Geometry n What is the length of side ‘n’ in the triangle at the right? Form ratios of corresponding sides: Use any two ratios to form a.

6.7Circumference and Arc Length Theorem 6.19 The circumference C of a circle is C = ____ or C = _____, where d is the diameter of the circle and r is.

6.7 Circumference & Area Notes. Circumference The distance around a circle. Do you remember the formula??? C = 2  r or C =  d * Always use the  button.

Circumference and Area of a Circle. Diameter Radius centre What is the formula relating the circumference to the diameter?

Quick Start Expectations 1.Fill in planner and HWRS HW: WS – Area & Circumference 2.Get a signature on HWRS 3.On desk: journal, HWRS, pencil, pen 4.Warm.

Areas of Circles and Sectors

10.4 Area and Circumference. Solving Area Problem Find the area of polygon shown at right. Solution: A = (3)(13)f 2 + (3)(6 + 3)f 2 = 39f f 2 =

9-5 Area of Circles Course 2 Warm Up Warm Up Problem of the Day Problem of the Day Lesson Presentation Lesson Presentation.

The area of the circle is about 227 m 2. COURSE 2 LESSON 8-4 Find the area of the circle to the nearest unit. = (8.5) 2 Substitute 8.5 for the radius.

Circumference and area of circles Pick up your calculator for today’s notes.

Outline Sec. 2-1 Direct Variation Algebra II CP Mrs. Sweet.

Recognising formulae A formula gives you a way to work out the value of something given other information. You use formulae across the curriculum. Which.

February 2, 2015 What are we doing today? 6.1 and 6.2 Review Due: Tomorrow Target To find the perimeter and area of rectangles and parallelograms. Question.

1.4 – Rewrite Formulas and Equations. Example 1: Solve the formula C = 2pir for r. Then find the radius of a circle with a circumference of 44 inches.

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.

Making graphs and solving equations of circles.

Quick Start Expectations 1.Fill in planner and HWRS HW: WS: Check-up 2 2.Get a signature on HWRS 3.On desk: journal, HWRS, LS packet, bin, calculators.

Investigation 7.1 Pricing Pizza Tenika Earline Lisa Byron.

Section 9-3 Circles Objectives I can write equations of circles I can graph circles with certain properties I can Complete the Square to get into Standard.

Warmup 10-1 For the following questions, use the equation, h(t) = -5t t Find the height of the object at 5 seconds, or h(5). 2. What is.

Question 1 Write the equation of the circle: Center: (-7, 14) Area: 81π.

Circumference Review. Review What is the relationship between a radius and a diameter? What does a circumference measure? What formulas do we use to calculate.

Do now: Work out the circumferences and areas of these circles 10 cm 12 cm 9 cm 2 cm 1.5 cm.

Warm-up 8.5 Area of Circles and 8.1 to 8.4 Quiz. Answers to H.W. pg 443 #1-8.

Calculator Tricks Magic Buttons for the TI-30Xa. Squares Squared 5 2 A = s 2 (area of a square) Find the following: 1.12 squared 2.Area of a square with.

Quick Start Expectations 1.Fill in planner and HWRS HW: WS: Circles: Area & Circumference + SBAC practice 2.Get a signature on HWRS 3.On desk: journal,

WARM UP 1)Find the area of an equilateral triangle with radius 2)Find the area of a regular hexagon with perimeter 72. 3)Find the area of a square with.

Geometry :. In this lesson, you will learn how to find:

Find the surface area of a sphere

Warmup 10-2 For 1-2, write an equation of a circle in standard form for the given information. 1. Center = (7, 0) and r = 4  3 2. Center = (8, -3) and.

AREA AND PERIMETER FORMULA TUTORIAL QUIZ. FORMULA MENU  Area of Square Area of Square  Area of a Circle Area of a Circle  Radius of a Circle Radius.

Learning Target: I can find the unit rate and the constant of proportionality from a graph, table, and equation. Homework: Complete notes on p.11 for the.

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

6 th Grade Math: Chapter 2 LEARNING GOAL Students will understand variables, expressions, and equations by being able to do the following: Identify and.

How to Find the Area of a Circle by : Rachel Sorenson.

AREA OF A CIRCLE Learning Target 4: I can solve problems using area and circumference of a circle.

Circles OCR Stage 6.

Homework: Moving Straight Ahead INV. 3: SOLVING EQUATIONS

SS 3.4 Additional Practice w/ Similar Figures 1) Teaching Target: I can use equivalent ratios to compare corresponding sides of similar rectangles. 2)

Height = 5 cm Width = 10.5 cm Length = 21.5 cm What is the Surface Area of this Kleenex Box? Dimensions: 21.5 cm x 10.5 cm x 5cm FILLING & WRAPPING 1.3.

18 Feb 2011 Warm UP– silently please 1) HOMEWORK DUE NEXT CLASS: pg. 112: # 6, 9, 20 - write basic information and clearly show all your steps so that.

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

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.

What is the constant of proportionality of the line represented by the equation What is the y-intercept of the line represented by the equation 2323 y.

WDYE? 4.1: Drawing Area Models to Find the Sample Space Learning Target: I will use an area model to represent a probability situation. HW: Complete the.

Circle Equations. Definitions Circle: The set of all points that are the same distance from the center Radius: a segment whose endpoints are the center.

6.10 Formulas. DIRECTIONS 1. Take out a sheet of paper and write your name on it. 2. Write the problem down but do not solve. 3. When the Teacher says.

Bell Work: Simplify 3√5√5. Answer: 15 LESSON 79: TRANSFORMING FORMULAS.

March 8 th,  Problem 1) A) What is the formula for the area of a circle? B) What is the formula for the circumference of a circle? C) How do these.

FILLING & WRAPPING 2.1 Learning Target: I will determine surface area and volume of prisms. HW: Complete the FW Investigation 2 Pg. 3 Cold Cans and Correct.

Math CC7/8 – Mar. 2 Math Notebook:

Check your understanding!

FW 3.4: More Circle Practice

Warm up – Solve by Completing the Square

FW : Area of a Circle 1) Learning Target: I will find the area of a circle by estimating and squaring a circle. 2) HW: Inv. 2 Day 4 FW

WDYE? 3.2: Analyzing Fairness

FILLING & WRAPPING 1.4- Scaling Up Prisms **QUIZ Thursday**

Find the Area of a Shaded Region

Presentation transcript:

FW 3.2: Area of a Circle Learning Target: I will find the area of a circle by estimating and squaring a circle. HW: Complete Inv. 3.2 pkt p. 6 and CORRECT with the Zaption video 3.2: Area of a Circle Warm Up: 1) Solve the equation: -3(m - 2) = 12 -3m + 6 = = m = 6 ÷ -3 ÷ - 3 m = - 2 2) Find the circumference if the radius is 4.5 in. Formula: C = d(3.14) d = 2r C = 2(4.5) (3.14) C = 9(3.14) C = in.

p. 4

12 in 9 in 15 in 4.5 in 6 in 7.5 in ≈ 64 in² ≈ 113 in² ≈ 177 in² To answer this question, the owner uses scale models of the different size pizzas:

12 in 9 in 15 in 4.5 in 6 in 7.5 in Approx. 64 in² Approx. 113 in² Approx. 177 in² As the diameter increases, the area increases. They are not increasing at a constant rate – as you increase the diameter by 3 inches each time, you do not increase the volume by the same amount each time (first you increase the area by about 49 inches, then you increase the area by about 64 inches). It should increase by about 81 inches to an area of 258 in². If you calculate the price based on area, then the medium pizza should be priced at (113/64)($6.00), or about $ The large pizza should be priced at (177/64)($6.00), or about $16.60.

6 units 36 ut² ≈ 113 ut² About 3 radius sq. 4 units 16 ut² ≈ 50 ut² About 3 radius sq. 3 units 9 ut² ≈ 28 ut² About 3 radius sq. Link to Video About Radius Squares Method

The area of a circle is equal to about 3 of the radius square areas. ==

A = Area = 3 x 8 x 8 = 192 square units

A fun way to remember formulas for circumference and area of a circle…

FW 3.2: Area of a Circle Did I reach my Learning Target? I will find the area of a circle by estimating and squaring a circle. HW: Complete Inv. 3.2 pkt p. 6 and CORRECT with the Zaption video 3.2: Area of a Circle