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Similar Figures b y Mrs. Byford. We will Learn to use ratios to determine if two figures are similar . Similar Figures. Octahedral fluorite is a crystal found in nature. It grows in the shape of an octahedron, which is a solid figure with eight triangular faces.
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Similar Figures by Mrs. Byford We will Learnto use ratios to determine if two figures are similar.
Similar Figures Octahedral fluorite is a crystal found in nature. It grows in the shape of an octahedron, which is a solid figure with eight triangular faces. The triangles in different-sized fluorite crystals are similar figures.
~ means the figures are similar When naming similar figures, list the letters of the corresponding vertices in the same order. For example ∆ABC ~ ∆DEF. E B C D A F
Matching sides of two or more polygons are called correspondingsides, and matching angles are called corresponding angles. Corresponding angles E B 82◦ 82◦ 55◦ 55◦ 43◦ 43◦ F A D C Corresponding sides
A side of a figure can be named by its endpoints, with a bar above. AB Without the bar, the letters indicate the length of the side. How do I name the side of a figure?
AB corresponds to ED. BC corresponds to EF. AC corresponds to DF. Identify the corresponding sides in the pair of triangles. Then use ratios to determine whether the triangles are similar. E 16 in 10 in A C 28 in D 7 in 4 in 40 in F B Now let's determine if the ratios are proportional So make the ratios of the corresponding sides and see if they are equal = = , they are simplify to so they are equal!
M P 100 m 80° 65° 60 m 47.5 m 125° 90° O 80 m N Q T 400 m 80° 65° 240 m 190 m 125° 90° S R 320 m Tell whether the figures are similar. Are the angles equal? Yes! So….. Are the sides proportional? Yes! All the ratios of the corresponding sides are equal to
Tell whether the figures are similar. Are the angles equal? Are the sides proportional?
59° 59° 35° 86° 86° 35° Insert Lesson Title Here Tell whether the figures are similar. Remember to ask yourself those two questions….. 1. similar
119° 107° 55° 79° 135° 107° 38° 80° Insert Lesson Title Here Tell whether the figures are similar. Remember to ask yourself those two questions….. 2. not similar