Free Exterior Angle Theorem Worksheet

Ten exterior-angle-theorem problems with a full answer key, ready to print.

Answer key included
Name: Date:
Exterior Angle Theorem
1.
The two remote interior angles of a triangle measure 56∘56^\circ and 67∘67^\circ. Find the measure of the exterior angle.
56∘56^\circ
67∘67^\circ
x∘x^\circ
2.
The two remote interior angles of a triangle measure 39∘39^\circ and 44∘44^\circ. Find the measure of the exterior angle.
39∘39^\circ
44∘44^\circ
x∘x^\circ
3.
The two remote interior angles of a triangle measure 44∘44^\circ and 82∘82^\circ. Find the measure of the exterior angle.
44∘44^\circ
82∘82^\circ
x∘x^\circ
4.
The two remote interior angles of a triangle measure 50∘50^\circ and 93∘93^\circ. Find the measure of the exterior angle.
50∘50^\circ
93∘93^\circ
x∘x^\circ
5.
The two remote interior angles of a triangle measure 20∘20^\circ and 57∘57^\circ. Find the measure of the exterior angle.
20∘20^\circ
57∘57^\circ
x∘x^\circ
6.
The two remote interior angles of a triangle measure 53∘53^\circ and 67∘67^\circ. Find the measure of the exterior angle.
53∘53^\circ
67∘67^\circ
x∘x^\circ
7.
The two remote interior angles of a triangle measure 51∘51^\circ and 57∘57^\circ. Find the measure of the exterior angle.
51∘51^\circ
57∘57^\circ
x∘x^\circ
8.
The two remote interior angles of a triangle measure 78∘78^\circ and 91∘91^\circ. Find the measure of the exterior angle.
78∘78^\circ
91∘91^\circ
x∘x^\circ
9.
The two remote interior angles of a triangle measure 29∘29^\circ and 59∘59^\circ. Find the measure of the exterior angle.
29∘29^\circ
59∘59^\circ
x∘x^\circ
10.
The two remote interior angles of a triangle measure 58∘58^\circ and 86∘86^\circ. Find the measure of the exterior angle.
58∘58^\circ
86∘86^\circ
x∘x^\circ
Andy · alldayeverydaymath.com
Name: Answer KeyDate:
Exterior Angle Theorem
1.
The two remote interior angles of a triangle measure 56∘56^\circ and 67∘67^\circ. Find the measure of the exterior angle.
56∘56^\circ
67∘67^\circ
x∘x^\circ
Answer: 123∘123^\circ
2.
The two remote interior angles of a triangle measure 39∘39^\circ and 44∘44^\circ. Find the measure of the exterior angle.
39∘39^\circ
44∘44^\circ
x∘x^\circ
Answer: 83∘83^\circ
3.
The two remote interior angles of a triangle measure 44∘44^\circ and 82∘82^\circ. Find the measure of the exterior angle.
44∘44^\circ
82∘82^\circ
x∘x^\circ
Answer: 126∘126^\circ
4.
The two remote interior angles of a triangle measure 50∘50^\circ and 93∘93^\circ. Find the measure of the exterior angle.
50∘50^\circ
93∘93^\circ
x∘x^\circ
Answer: 143∘143^\circ
5.
The two remote interior angles of a triangle measure 20∘20^\circ and 57∘57^\circ. Find the measure of the exterior angle.
20∘20^\circ
57∘57^\circ
x∘x^\circ
Answer: 77∘77^\circ
6.
The two remote interior angles of a triangle measure 53∘53^\circ and 67∘67^\circ. Find the measure of the exterior angle.
53∘53^\circ
67∘67^\circ
x∘x^\circ
Answer: 120∘120^\circ
7.
The two remote interior angles of a triangle measure 51∘51^\circ and 57∘57^\circ. Find the measure of the exterior angle.
51∘51^\circ
57∘57^\circ
x∘x^\circ
Answer: 108∘108^\circ
8.
The two remote interior angles of a triangle measure 78∘78^\circ and 91∘91^\circ. Find the measure of the exterior angle.
78∘78^\circ
91∘91^\circ
x∘x^\circ
Answer: 169∘169^\circ
9.
The two remote interior angles of a triangle measure 29∘29^\circ and 59∘59^\circ. Find the measure of the exterior angle.
29∘29^\circ
59∘59^\circ
x∘x^\circ
Answer: 88∘88^\circ
10.
The two remote interior angles of a triangle measure 58∘58^\circ and 86∘86^\circ. Find the measure of the exterior angle.
58∘58^\circ
86∘86^\circ
x∘x^\circ
Answer: 144∘144^\circ
Andy · alldayeverydaymath.com

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About this worksheet

The exterior angle of a triangle equals the sum of the two remote interior angles. Students practice that relationship directly — a common test question that trips up learners who only memorized the 180-degree rule.

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