# Perimeters and Areas of Similar Figures Geometry 8

- Slides: 30

Perimeters and Areas of Similar Figures Geometry 8 -6

• Get your supplies – Graph Paper Exploration

• Draw a Rectangle on your graph paper • Calculate its area (in graph units) Exploration

• Multiply each dimension of the rectangle by a scale factor and draw the new larger (smaller) rectangle • Calculate its area Exploration

• What is the ratio of the side lengths? • What is the ratio of the areas? • How many smaller rectangles would it take to fill the larger rectangle? Exploration

• Calculate the area of these two similar triangles 108 12 What is the ratio of the side lengths? What is the ratio of the areas? Exploration

• Calculate the area of these two circles is terms of pi 9π 4π What is the ratio of the radii? What is the ratio of the areas? Exploration

• If corresponding side lengths of two similar polygons or the radii of two circles compare in the ratio a/b, then the areas compare in the ratio a 2/b 2. Proportional Area

Example

Example

Example

Example

Practice

Practice

Practice

Practice

Practice

Practice

Practice

Practice

Practice

Sample Problems

Sample Problems

Sample Problems

Sample Problems

Sample Problems

Sample Problems

Sample Problems

Sample Problems

• Pages 456 – 459 • 2 -18 even, 26, 39, 50, 51 Homework

- Lesson 10-4 perimeters and areas of similar figures
- Complete each proportion ab/bm= /cd
- 10-4 perimeters and areas of similar figures
- Perimeters and areas of similar figures quiz
- Composite figures definition
- Similar and congruent shapes
- Areas of similar figures worksheet
- Areas of similar figures
- Similar figures geometry definition
- Auditing networks perimeters and systems
- Network perimeters
- Areas of regular polygons and composite figures
- 11-4 areas of regular polygons answers
- 12-5 areas and volumes of similar solids
- Plane shape
- Pentagon plane figure or solid figure
- Quiz 6-1 ratios and similar figures
- Similar triangles and polygons
- Indirect measurement using similar triangles
- Similar figures
- Quiz 6-1 ratios and similar figures
- Similar figures and indirect measurement
- Similar figures proportions
- 2-8 proportions and similar figures
- Similar shapes and scale drawings
- Similar figures vocabulary
- Lewis dot structure and molecular geometry
- Similar shapes and scale drawings worksheet
- Proving figures are similar using transformations
- 11-3 corresponding parts of similar figures
- Similar figures word problems