# Exterior Angles Worksheets

These freeÂ geometry worksheetsÂ will introduce you to the Exterior Angle Sum Theorem, as you find the measurements of the exterior angles of a triangle. Â The exterior, or outside, angles of a triangle are always congruent to the two non-adjacent, interior angles of the triangle. Â In plain English, the outside angles is equal to sum of the two inside angles that are farthest away.

Like most of the worksheets at www.imathworksheets.com, this is a progressive series. Â That means we start with the easy problems and add a new twist to each successive worksheet. Â Of course, answer keys are provided as well.

Exterior Angles of a Triangle Worksheet 1Â - ThisÂ angle worksheetÂ features 12 different triangles, all with one clearly identified exterior angle, represented by x. Â The measurements of the three interior angles are given. Â Simply add the two non-adjacent angles, and you have found the measure of the exterior angle.

Exterior Angles of a Triangle Worksheet 2Â - ThisÂ angle worksheetÂ features 12 different triangles, all with one or more exterior angle. Â Some additional angle measures are given to make sure you can identify the angles that you need, the two non-adjacent angles.

Exterior Angles of a Triangle Worksheet 3Â - You’ll need to use all of your knowledge about exterior and interior angles for this 12 problemÂ angle worksheet.Â  Sometimes you’ll Â need to use the exterior angle to find the interior angle, and vice-versa. Â Fortunately, no algebraic expressions are thrown in, yet.

Exterior Angles of a Triangle Worksheet 4Â - This 12 problemÂ angle worksheetÂ represents the missing angles with algebraic expressions likeÂ 3x andÂ 7x – 4. Â You’ll need to use your knowledge of exterior angles to set up equations and solve for x. Â Then, you’ll have to plug your solution into each expression to find the missing angles.

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### 1 Comment

1. #### Kersha wells

/  June 8, 2014

I think this is a great way to help people to understand maths better.