Classifying Triangles Angle Measures of Triangles.
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Transcript of Classifying Triangles Angle Measures of Triangles.
![Page 1: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/1.jpg)
Classifying Triangles
Angle Measures of Triangles
![Page 2: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/2.jpg)
Triangle
• A triangle is a figure formed by three segments joining three noncollinear points.
![Page 3: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/3.jpg)
Classifying Triangles by Sides
• Equilateral Triangle
• Isosceles Triangle
• Scalene Triangle
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Equilateral Triangle
• An equilateral triangle has three congruent sides.
![Page 5: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/5.jpg)
Isosceles Triangle
• An isosceles triangle has at least two congruent sides.
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Scalene Triangle
• A scalene triangle has no congruent sides.
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Classify the triangle by its sides.
![Page 8: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/8.jpg)
Classification of Triangles by Angles
• Equiangular triangle
• Acute triangle
• Right triangle
• Obtuse triangle
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Equiangular Triangle
• An equiangular triangle has three congruent angles.
![Page 10: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/10.jpg)
Acute Triangle
• An acute triangle has three acute angles.
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Right Triangle
• A right triangle has one right angle.
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Obtuse Triangle
• An obtuse triangle has one obtuse angle
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Classify the triangle by its angles.
![Page 14: Classifying Triangles Angle Measures of Triangles.](https://reader031.fdocuments.net/reader031/viewer/2022020714/56649e865503460f94b8a17d/html5/thumbnails/14.jpg)
Vertex
• A vertex of a triangle is a point that joins two sides of the triangle.
• The side across from an angle is the opposite side.
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Name the side that is opposite the angle.
• Angle J
• Angle K
• Angle L
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Triangle Sum Theorem• The sum of the measures of the angles of a
triangle is 180º.• In ΔABC, mA + m B + m C = 180º
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Find the measure of the missing angle.
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Corollary to the Triangle Sum Theorem
• The acute angles of a right triangle are complementary.
• In ΔABC, if m C = 90º, then
m A + m B= 90º
A
CB
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ΔABC is a right triangle. Find the measure of angle A.
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Interior Angles
• When the sides of a triangle are extended, other angles are formed.
• The three original angles are the interior angles.
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Exterior Angles
• The angles that are adjacent to the interior angles are the exterior angles.
• It is common to show only one exterior angle at a vertex.
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Exterior Angles Theorem
• The measure of an exterior angle of a triangle is equal to the sum of the two remote interior angles.
• m 1 = m A + m B
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Find the measure of angle 1.