Similarity
Overview
Two figures are similar when they have the same shape but not necessarily the same size: one is a scaled copy of the other. Every pair of matching lengths is in the same ratio, the scale factor, which lets you find a missing length from a single comparison.
In this lesson you will recognize similar figures, use the scale factor to calculate lengths, and (Extended) see how areas scale by the square of the scale factor and volumes by its cube. That area and volume rule is a favorite of examiners.
Objectives
- Recognize similar figures and calculate lengths of similar figures, and (Extended) relate the areas and volumes of similar figures.
Audio Lesson
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Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Similarity. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Two similar triangles have matching sides 4 and 6. The scale factor is: A. 1.2 B. 1.5 C. 2 D. 2.4 Answer: B
- If the length scale factor is k, the area scale factor is: A. k B. 2k C. k squared D. k cubed Answer: C
- If the length scale factor is k, the volume scale factor is: A. k B. k squared C. k cubed D. 3k Answer: C
- Similar figures have corresponding angles that are: A. doubled B. equal C. halved D. supplementary Answer: B
- Two similar solids have lengths in ratio 2:3. The volume ratio is: A. 2:3 B. 4:9 C. 8:27 D. 6:9 Answer: C
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