Exterior Angle Theorem

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Presentation transcript:

Exterior Angle Theorem Interior Angles Exterior Angles Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

The measure of the exterior angle is equal to the sum of two nonadjacent interior angles (Remote Interior Angles: <1 and <2) 1 m1+m2 =m3 2 3 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

What is this? When do you use it? Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

x = 81° Find the value of x. 43 x 38 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

x = 76° Find the value of x. 72 148 x Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

x = 100° Find the value of x. x 50 50 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

x = 110° Find the value of x. 50 x 60 70 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

Which is larger? 1 or 3? 2 3 1 3 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?

Which is larger? 2 or 3? 2 3 1 3 Essential Question: How do the external angles of a triangle relate to the two remote interior angles?