Similar Figures You will need two different colored highlighters Not all slides are used in the notes
Similar figures have the same shape but not necessarily the same size. When naming similar figures, list the letters of the corresponding vertices in the same order. In the previous table ∆ABC ~ ∆DEF. Writing Math SIMILAR FIGURES Two figures are similar if The measures of their corresponding angles are equal. The ratios of the lengths of the corresponding sides are proportional.
Matching sides of two or more polygons are called corresponding sides, and matching angles are called corresponding angles. 82◦ Corresponding angles D E F Corresponding sides A B C 82◦ 55◦43◦ 55◦ 43◦
A B C F G H Determine if the shapes are proportional. Do not rely on a visual 10 in 4 in 7 in 16 in 28 in 40 in 1. Highlight corresponding sides 2. Set up proportions Small Large == 4 in 16 in 10 in 28 in 7 in 40 in 3. Simplify == 1 in 4 in 1 in 4 in 1 in 4 in
The rectangle on the left is similar in shape to the rectangle on the right. Find the width of the right rectangle. 3 cm 6 cm 12 cm Let w = the width of the right rectangle = 3w3w 6 ·w = 12 · 3 6w = 36 6w66w6 = 36 6 w = 6 The right rectangle is 6 cm wide. 1. Write a proportion 2. Solve the proportion. ?
City officials want to know the height of a traffic light. Estimate the height of the traffic light = h Write a proportion. Use compatible numbers to estimate ≈ 49 h Simplify. 9h ≈ 245 The traffic light is about 30 feet tall ft ft h ft ≈ 49 h Solve proportions. h ≈ 27
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Similar Figures You will need two different colored highlighters Not all slides are used in the notes Date ____________
Matching sides of two or more polygons are called corresponding sides, and matching angles are called corresponding angles. 82◦ Corresponding angles D E F Corresponding sides A B C 82◦ 55◦43◦ 55◦ 43◦
A B C F G H Determine if the shapes are proportional. Do not rely on a visual Small Large == 3. ==
The rectangle on the left is similar in shape to the rectangle on the right. Find the width of the right rectangle. 3 cm 6 cm 12 cm Let w = the width of the right rectangle. = ? = = = =
City officials want to know the height of a traffic light. Estimate the height of the traffic light. = ≈ ≈ ft ft h ft ≈