Home / Worksheets / Grade 11 / Math / Triangle Sum Theorem Worksheet

Triangle Sum Theorem Worksheet

A Grade 11 math worksheet focusing on the Triangle Sum Theorem, including various problem types to reinforce understanding of triangle angle properties.

Grade 11 Math GeometryTriangle Sum Theorem
Use This Worksheet

Includes

Short AnswerMultiple Choice2 CustomFill in the BlanksTrue / False

Standards

CCSS.MATH.CONTENT.HSG.CO.C.10

Topics

MathGeometryTrianglesTriangle Sum TheoremGrade 11
8 sections · Free to use · Printable
← More Math worksheets for Grade 11

Triangle Sum Theorem Practice

Name:

Date:

Score:

Read each question carefully and answer to the best of your ability. Show all your work for full credit.

1. What is the Triangle Sum Theorem? Explain it in your own words.

2. In triangle ABC, if angle A = 45° and angle B = 60°, what is the measure of angle C?

a

65°

b

75°

c

85°

d

95°

3. Find the value of x in the triangle below.

x°70°50°

4. The sum of the interior angles of any triangle is always   degrees.

5. An exterior angle of a triangle is equal to the sum of the two   interior angles.

6. A triangle can have two obtuse angles.

T

True

F

False

7. In triangle DEF, the measure of angle D is (2x + 10)°, angle E is (3x - 20)°, and angle F is (x + 30)°. Find the value of x and the measure of each angle.