Triangle Review
Triangle Types
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Use the interactive animation below to manipulate vertex "C". Try to form the 6 triangle types from above.
Interior Angles of a Triangle
Recall that the interior (inside) angles of a triangle add up 180. Manipulate the triangle below to verify.
Summary
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Exterior Angles of a Triangle.
There are two exterior (outside) angle relationships to consider for triangles. For the first relationship, the exterior angles of a triangle all add up to 360.
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In the second relationship, an exterior angle equals the sum of the two opposite interior angles. Use the animation below to illustrate. In the animation below, drag Point A (or BAC) to verify. For the second animation, drag the slider to visually observe the relationship.
Summary
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