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7-1B Similar Polygons. What is a proportion? What are proportions used for in Geometry? What Geometry symbol is used for “is similar to”? What similar figure is used for travel?. Definition. Proportion--an equation stating that two ratios are equal. Geometry Symbols.
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7-1B Similar Polygons What is a proportion? What are proportions used for in Geometry? What Geometry symbol is used for “is similar to”? What similar figure is used for travel?
Definition • Proportion--an equation stating that two ratios are equal.
Geometry Symbols The symbol ~ means “is similar to”. The order of the letters in the similarity correspondence indicates the corresponding parts. ABC ~ XYZ
ABCDE ~ MNOPQ. Name all pairs of congruent corresponding angles, and write proportions using the pairs of corresponding sides. N O E A D M P C B Q
Write the similarity correspondence. Name all pairs of congruent corresponding angles and write proportions using the pairs of corresponding sides. I 45 Q R 15 X F Y 53° 5 10 75 25 60 20 6 3 V W 37° 30 E 4 G T 90 S J H 8
Map Reading The scale on a map relates the size of an object on the map to its actual size. Where do you find the scale on a map? Use the scale and algebra to find the distance between Mishawaka and Kokomo.
Given: FGHJ~WXYZFind YZ W Z Since the length of the corresponding sides are proportional, set up a proportional statement. J 12 F 9 X G 14 H Y
EFGH ~ KNML • Find the measures of angles E, G, and N. • Find x, y, and z. • What is the similarity ratio of KNML to EFGH? N F X 43° 10 35 E 4 143° z G K H 6 67° 10 107° L y M x = 14, y = 15, z = 25 5/2
What is a proportion? A proportion is an equation stating that two ratios are equal. • What are proportions used for in Geometry? To find the length of the sides of similar figures. • What Geometry symbol is used for “is similar to”? ~ • What similar figure is used for travel? Maps
Assignment 7-1B p. 471, 1-8, 11-13, 28-33