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Author:
Todd Parks

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Tutorial

We need to remember that ** ALL** triangles (right triangles, obtuse triangles, and acute triangles), their interior angles

Also, two angles that are adjacent to each other (next to each other), that form a straight line, also add up to 180 degrees. We see this when a side of a triangle is extended. The interior angle and exterior angle add up to 180 degrees.

We already know our ** triangle angle theorem**, which is the three interior angles of any triangle add up to 180 degrees.

Now we have our *straight angle theorem* which states that any straight line will also equal 180 degrees.

In the video, Mr. Parks goes over a couple of the examples in lesson 14 covering how to find exterior and interior angles of a triangle.

Here is the IXL target that coordinates with **exterior angles of triangles** in lesson 14 of module 2.

Practice and discover before trying the ** quiz** above.