If a triangle has angles measuring 60° and 70°, what is the measure of the third angle?

If a triangle has angles measuring 60° and 70°, what is the measure of the third angle?

• A. 50°
• B. 40°
• C. 30°
• D. 80°

Answer: (B)

In a triangle, the sum of all interior angles is always equal to 180°. To find the measure of the third angle when two angles are known, you can subtract the sum of the known angles from 180°. In this case, you have angles measuring 60° and 70°. First, add these two angles together: 60° + 70° = 130° Next, subtract this sum from 180° to find the measure of the third angle: 180° - 130° = 50° This calculation shows that the measure of the third angle is 50°. Understanding this concept is essential in solving triangle-related problems, as it relies on the fundamental property of triangles that all angles must sum to 180°.

In a triangle, the sum of all interior angles is always equal to 180°. To find the measure of the third angle when two angles are known, you can subtract the sum of the known angles from 180°.

In this case, you have angles measuring 60° and 70°. First, add these two angles together:

60° + 70° = 130°

Next, subtract this sum from 180° to find the measure of the third angle:

180° - 130° = 50°

This calculation shows that the measure of the third angle is 50°. Understanding this concept is essential in solving triangle-related problems, as it relies on the fundamental property of triangles that all angles must sum to 180°.