2.8 E Proportions and Similar Figures.notebook
November 06, 2015
2.8 Proportions and Similar Figures
Objective: Be able to find missing lengths in similar figures and to
use similar figures when measuring indirectly.
Similar figures: figures that have the same shape but not necessarily the same size. The side lengths are always proportional, and the angles are always congruent.
We use proportions to solve for missing information.
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
D
A
10
5
4
B
E
3
F
C
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
A student who is 5.25 ft tall is standing next to a tree. The shadow of the student is 20 ft and the shadow of the tree is 80 ft. What is the height of the tree? Sep 25­11:44 AM
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
One inch represents 12 miles on a map. If the distance between two buildings is 4 in. on the map, what is the actual distance?
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
A model of a new campus building is 5 inches tall. If 1 inch represents 8.5 feet, how tall will the building be?
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
Lesson Check: pg. 133 #'s 1
1. You use a photocopier to enlarge a drawing of a right triangle with a base of 13 cm and a height of 7 cm. The enlarged triangle has a height of 17.5 cm. A. what is the base of the enlarged triangle?
B. What is the scale?
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2.8 E Proportions and Similar Figures.notebook
November 06, 2015
Homework:
Practice 2.8
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