Test your understanding of finding missing angles in a triangle.

Try to answer the questions before checking the answers at the bottom of the page.

Question 1

A triangle has angles:

60°, x, 30°

Find x.

A) 80°
B) 90°
C) 100°

Question 2

A triangle has angles:

x, 90°, 40°

Find x.

A) 40°
B) 50°
C) 60°

Question 3

A triangle has angles:

50°, 100°, x

Find x.

A) 20°
B) 30°
C) 40°

Question 4

A triangle has angles:

x, 60°, x

Find x.

A) 50°
B) 60°
C) 70°

Question 5

A triangle has angles:

x, 3x, 2x

Find x.

A) 20°
B) 30°
C) 40°

Answers

1️⃣ B – 90°

2️⃣ B – 50°

3️⃣ B – 30°

4️⃣ B – 60°

5️⃣ B – 30°

Practice

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Continue Learning

1. Types of Triangles
2. Triangles (Basics)
3. Sum of Angles of a Triangle is 180° (Proof)
4. Find the Missing Angle of a Triangle
5. Sum of Exterior Angles of a Triangle (Proof)
6. Exterior Angle Theorem of a Triangle
7. Two Exterior Angles at a Vertex are Equal (Proof)
8. Two Exterior Angles are Equal at a Vertex (Quick Proof)

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