Lesson 4
1. Lesson 4
1.2. Explore 2
Module 6: Proportional Reasoning
Whether an object is being enlarged or reduced, a scale factor ensures that the enlargement or reduction of an object is proportionally consistent with the original dimensions. In similar objects, the ratio of any two corresponding measurements or dimensions will be a constant number (i.e., the scale factor).
Read “Example 3: Determining scale factor” on page 470 of your textbook. Why is it important that both measurements be expressed in the same unit?
Choose one of the following options to explore examples involving the use of scale.
Option 1: In your favorite Internet search engine, type in “Ratio and Scale Absorb Learning.” The guided search should take you to the Absorb website with online courses. This resource will guide you through examples of how scale is used to create models and drawings.
Option 2: Use the Scale Factor applet to investigate how scale factor is used to produce proportional enlargements and reductions.
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Self-Check 2
- Complete “Check Your Understanding” questions 1 and 2 on page 471 of your textbook. Answer
- Complete “Check Your Understanding” question 2 on page 490 of your textbook. Answer
Read “Example 1: Determining if two objects are similar” on page 484 of your textbook. How does Sandeep determine that the pans are proportional?
Self-Check 3
Complete “Check Your Understanding” question 1 on page 489 of your textbook. Answer
Try This 1
Go to the Internet and enter the keywords “Scale Factor X.” These keywords should take you to a website with a game, “Scale Factor X,” which allows you to practise your skills on proportion and scale factors. See if you can complete your mission before the Scaliens know you are there!