# Worksheet: Sum of Angles of a Triangle

In this worksheet, we will practice finding a missing angle in a triangle given the two other angles using the triangle angle-sum theorem.

**Q1: **

In triangle , we have and . What is ?

**Q4: **

Complete the following: The sum of measures of the interior angles of a triangle is .

**Q5: **

Complete the sentence: The measure of a straight angle is the sum of the measures of the interior angles of a triangle.

- A less than
- B equal to
- C greater than

**Q6: **

What is the sum of the measures of the two acute angles in a right-angled triangle?

**Q7: **

Calculate the value of .

**Q8: **

In triangle , and . What is ?

**Q9: **

Find .

**Q10: **

The given design is carved on a wooden board. If is a right angle, determine the values of , , and .

- A , ,
- B , ,
- C , ,
- D , ,

**Q11: **

In triangle , the measures of angles in degrees at , , and are , , and 43, respectively. Find and .

- A ,
- B ,
- C ,
- D ,

**Q13: **

In triangle , and . Find .

**Q14: **

In , . Determine .

**Q15: **

In the figure below, given that is a rectangle, determine .

**Q16: **

If is a triangle in which and . Calculate the measures of angles , , and .

- A , ,
- B , ,
- C , ,
- D , ,

**Q17: **

In the triangle , , , and . Find the measure of each angle.

- A , ,
- B , ,
- C , ,
- D , ,
- E , ,

**Q18: **

Given that is a triangle in which , , and , determine .

**Q19: **

Find the measure of each angle in the triangle below.

- A , ,
- B , ,
- C , ,
- D , ,

**Q20: **

The figure shows a rectangle and a square . What is ?

**Q21: **

The sum of the measures of the angles of a triangle is . In a right triangle, what is the sum of the measures of the two acute angles?

**Q22: **

In , . If is an altitude of , find .

**Q23: **

If the ratio between the measures of the angles of a triangle is , determine the measures of the angles.

- A , ,
- B , ,
- C , ,
- D , ,
- E , ,

**Q24: **

Suppose that in the figure, and . Determine these two angles.

- A ,
- B ,
- C ,
- D ,
- E ,

**Q25: **

The measures of the angles in a triangle are in a ratio of . Work out the measures of these angles.

- A , ,
- B , ,
- C , ,
- D , ,
- E , ,