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Big Ideas:
An infinite amount of similar triangles can be created by three angles with a sum of 180 degrees.
Triangles can have multiple sides lengths, but the three angle measures remain the same. (This works only when the sides are multiplied by a scale factor.)
Students have learned the properties of triangles and how to classify triangles based on both their sides and angles. They also know how to construct an angle. Using these two skills, students will construct triangles given three angle measures. Students will learn that multiple triangles can be formed when given three angle measures with a sum of 180 degrees. Students need to understand that side length of a triangle can change, yet the angle measure can still remain the same.
Vocabulary: acute triangle, obtuse triangle, right triangle, scalene triangle, isosceles triangle, equilateral triangle
Special Materials:
Rulers and Protractors