lesson 19 computing actual areas from a scale drawing
TRANSCRIPT
Lesson 19Computing Actual Areas from a Scale
Drawing
Review
What is the difference between scale and scale factor?
Examples 1–3: Exploring Area Relationships
Use the diagrams below to find the scale factor and then find the area of each figure.
Example 1
Scale factor: _________ Actual Area = ______________ Scale Drawing Area = ________________ Ratio of Scale Drawing Area to Actual Area: _________
Example 2
Scale factor: _________
Actual Area = ______________ Scale Drawing Area = ________________ Ratio of Scale Drawing Area to Actual Area: _________
Example 3
Scale factor: _________ Actual Area = ______________ Scale Drawing Area = ________________ Ratio of Scale Drawing Area to Actual Area: _________
Why do you think it is squared as opposed to cubed or something else?
How might you use this information I working with scale drawings?
Suppose a rectangle has an area of 12 square m. If it is enlarged by a scale factor of three, what area would you predict the enlarged rectangle to have based on what you just concluded?
