Let's analyze the triangles from the image and solve for the missing angles:

Part a (non-right triangle):

• The given angles are both 60°.

• In any triangle, the sum of the interior angles is always 180°. Therefore, the missing angle can be calculated as:

  $180^\circ - (60^\circ + 60^\circ) = 60^\circ$

  So, the missing angle in triangle a is 60°.

Part b (right triangle):

• The given angles are 30° and 90°.

• Again, the sum of the angles in any triangle is 180°. Thus, the missing angle can be calculated as:

  $180^\circ - (90^\circ + 30^\circ) = 60^\circ$

  So, the missing angle in triangle b is also 60°.

Final Answers:

• a. The missing angle is 60°.
• b. The missing angle is 60°.

Would you like more details on any part of this explanation?

Here are 5 related questions:

1. Why do the angles of any triangle always add up to 180°?
2. What are the properties of equilateral triangles, like triangle a?
3. How do we classify triangles based on their angles?
4. What is the difference between right, acute, and obtuse triangles?
5. Can there be a triangle with two 90° angles?

Tip: In a right triangle, one angle is always 90°, and the sum of the other two angles must equal 90°.