What number of triangles can be formed using the set of interior angle measures below

Question

12°, 90°, 78°
One unique triangle
Many triangles
no triangles

Answer 1

To determine if the angles provided can form a triangle, we need to verify two conditions:

1. The sum of the angles must equal 180°.
2. Each angle must be greater than 0°.

Let's first check the sum of the given angles:

12° + 90° + 78° = 180°

Since the sum equals 180°, this satisfies the first condition.

Next, we check that all angles are greater than 0°:

• 12° > 0°
• 90° > 0°
• 78° > 0°

Since both conditions are satisfied, the set of angles can indeed form a triangle.

However, since the angles are fixed, only one unique triangle can be formed from them (as triangles with the same angle measures are considered congruent).

Thus, the answer is:

One unique triangle.