1 / 17

Course 2

Warm Up. Problem of the Day. Lesson Presentation. Lesson Quizzes. Course 2. Warm Up 1. What is the area of a figure made up of a rectangle with length 12 cm and height 4 cm and a parallelogram with length 12 cm and height 6 cm?

nolan-shepard
Télécharger la présentation

Course 2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Warm Up Problem of the Day Lesson Presentation Lesson Quizzes Course 2

  2. Warm Up 1. What is the area of a figure made up of a rectangle with length 12 cm and height 4 cm and a parallelogram with length 12 cm and height 6 cm? 2. What is the area of a figure consisting of a triangle sitting on top of a rectangle? The triangle has a base of 12 in. and height of 9 in., and the rectangle has a base of 12 in. and height of 5 in. 120 cm2 114 in2

  3. Problem of the Day If sixteen people sit, evenly spaced, in a circle for story time, who sits directly across from person 5? person 13

  4. Sunshine State Standards MA.7.G.4.1 Determine how changes in dimensions affect the perimeter [and] area…of common geometric figures and apply these relationships to solve problems.

  5. Additional Example 1: Comparing Perimeters and Areas Find how the perimeter and the area of the figure change when its dimensions change. = 1 inch Draw a model of the two figures on graph paper. Label the dimensions. The original figure is a 4  2 in. rectangle. The smaller figure is a 2  1 in. rectangle.

  6. P = 2(l + w)‏ P = 2(l + w). Additional Example 1 Continued Find how the perimeter and the area of the figure change when its dimensions change. Use the formula for perimeter of a rectangle. Substitute for l and w. = 2(4 + 2)‏ = 2(2 + 1) Simplify. = 2(6) = 12 = 2(3) = 6 The perimeter is 6 in. The perimeter is 12 in.

  7. A = lw = 4 x 2 = 2 x 1 Additional Example 1 Continued Find how the perimeter and the area of the figure change when its dimensions change. Use the formula for area of a rectangle. A = lw Substitute for l and w. Simplify. = 2 = 8 The area is 8 in2. The area is 2 in2. The perimeter is divided by 2, and the area is divided by 4.

  8. Check It Out: Example 1 Find how the perimeter and area of the figure change when its dimensions change. 8 in. 4 in. 2 in. 4 in. When the dimensions of the rectangle are multiplied by 2, the perimeter is multiplied by 2 and the area is multiplied by 4 or 2 . 2

  9. Multiply each dimension by 4. P = 10 cm P = 40 cm A = 6 cm2 A = 96 cm2 When the dimensions of the rectangle are multiplied by 4, the perimeter is multiplied by 4, and the area is multiplied by 16, or 42. Additional Example 2: Application Draw a rectangle whose dimensions are 4 times as large as the given rectangle. How do the perimeter and area change? 12 cm 3 cm 8 cm 2 cm

  10. Check It Out: Example 2 Draw a rectangle whose dimensions are 2 times as large as the given rectangle. How do the perimeter and area change? 5 cm 3 cm 10 cm 6 cm

  11. Check It Out: Example 2 Continued When the dimensions of the rectangle are multiplied by 2, the perimeter is multiplied by 2, and the area is multiplied by 4, or 2 . 2

  12. Additional Example 3: Application Mei works at a local diner whose speciality is making pancakes. She makes silver dollar pancakes with a diameter of 2 inches as well as regular pancakes with a diameter double that of the silver dollar pancakes. Does a regular pancake have twice the area of a silver dollar pancake? Explain. Use 3.14 for . Find the area of each pancake and compare. Silver: A = r2 Use the formula. Regular: A = r2 A(1)2 Substitute for r. A(2)2 A  1 Evaluate the power. A  4 A3.14 Multiply. A12.56

  13. Additional Example 3 Continued Mei works at a local diner whose speciality is making pancakes. She makes silver dollar pancakes with a diameter of 2 inches as well as regular pancakes with a diameter double that of the silver dollar pancakes. Does a regular pancake have twice the area of a silver dollar pancake? Explain. Use 3.14 for . The area of the silver dollar pancake is 3.14 in2, and the area of the regular pancake is 12.56 in2. When the diameter is doubled, the area is 22, or 4, times as great.

  14. Check It Out: Example 3 Rae is designing a can for a new line of soup products. The original can had a base diameter of 7 cm and her new design will be double that of the original base diameter. Will the new soup can take up double the shelf space of the original can? Explain. Use 3.14 for. 2 original can base ≈ 38.47 cm new can base ≈ 153.86 cm No, the can will take 2 , or four times the shelf space. 2 2

  15. Lesson Quizzes Standard Lesson Quiz Lesson Quiz for Student Response Systems

  16. Lesson Quiz Find how the perimeter and area of the triangle change when its dimensions change. The perimeter is multiplied by 2, and the area is multiplied by 4; perimeter = 24, area = 24; perimeter = 48, area = 96.

  17. Lesson Quiz for Student Response Systems 1. Identify how the perimeter and area of the triangle change when its dimensions change. A. the perimeter is multiplied by 2, and the area is multiplied by 4; perimeter 30, area = 30; perimeter 60, area = 120. B. the perimeter is multiplied by 2, and the area is multiplied by 4; perimeter 30, area = 60; perimeter 60, area = 120.

More Related