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Learning Log #8 Scale Factor. What is the Scale Factor?. ?. 5m. B. 20m. 64m. A. A. A. 256m. ?. Learning Log #8 - Scale Factor. Always start by asking yourself “ which side corresponds to which side ?”. This side corresponds to this side. Reminder
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Learning Log #8 Scale Factor What is the Scale Factor? ? 5m B 20m 64m A A A 256m ?
Learning Log #8 - Scale Factor • Always start by asking yourself “which side corresponds to which side?” This side corresponds to this side. Reminder You must always say Scale Factor with direction.Example: “The scale factor of B to A is…” 5m B 20m 64m A A A 256m And you need to ask yourself, what multiplied by 5 makes 20? Or you could simply do 20 ÷ 5 = 4. 4 is our scale factor from B to A because 5 * 4 = 20m. The reverse, A to B, 20 * ¼ = 5. We get ¼ by using the reciprocal of 4. Remember, Scale Factor is always expressed as multiplication not division.
Scale Factor from A to B is 1/6 because 30m * 1/6 = 5m24m *1/6 is 4m B to A is 6 because 5m * 6 = 30m4m * 6 = 24m SF & Perimeter Perimeter of B is 12m Scale Factor B to A is 6 P * SF = Perimeter of A 12m * 6 = 72m 72m is the perimeter of A B to A the Perimeter is 6 times larger. Learning Log #8 Scale Factor “How do they compare?” SF =* 1/6 4m 30m B 24m SF & Area Area of B is 6m² Scale Factor B to A is 6 & 6² = 36 Area * SF² = Area of A 36*6m² = 216m² B to A the area is 36 times larger. 3m 5m A A A 18m SF=*6 SF & Side Lengths The side-lengths from B to A are 6 times larger.
Scale Factor: Area & Perimeter • Perimeter 1st P * SF = 2nd P Variables Defined P = perimeter 1st P = 1st perimeter 2nd P = 2ndperimeter SF = Scale Factor • Area1st A * SF²= 2nd A Variables Defined A = Area 1st A = 1st Area 2nd A = 2nd Area SF = Scale Factor Angles And remember, if two images are similar the angles remain the same!