1. Similar Triangles Focus – Apply the properties of similar triangles and tomorrow, prove that triangles are similar. Lesson 8-3 WA State Standards: G.3.A and G.3.B
2. Congruent Triangles …have matching angles that are congruent. …have matching sides that are congruent. A B C D F E 100° 35° 45° 115 ft 150 ft 100 ft 150 ft 115 ft 100 ft 35° 100° 45°
3. Congruent Triangles …have matching angles that are congruent. …have matching sides that are congruent. A B C D F E 100° 35° 45° 115 ft 150 ft 100 ft 150 ft 115 ft 100 ft 35° 100° 45°
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8. Are they similar? Use Angle/Angle or AA Similarity . Two congruent angles show triangles are similar.
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10. Is ABC similar to AEF? A E F C B Sometimes it helps to separate the two triangles and look at each angle separately.
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16. Is ABC similar to AEF? If so, what Is the missing side? y 15 16 x 12 12 A B C E F
17. It often helps to separate the two attached triangles. y 15 16 x 12 12
18. Prove: A line drawn from a point on one side of a triangle parallel to another side forms a triangle similar to the original triangle.