The measures of two angles of a triangle are `72°` and `58°`. Find the measure of the third angle.

Answer

To find the measure of the third angle in a triangle when two angles are given, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given angles**: We have two angles of the triangle, which are 72° and 58°.

2. **Let the third angle be x**: Since we need to find the measure of the third angle, we can denote it as x degrees.

3. **Use the triangle angle sum property**: The sum of all angles in a triangle is always 180°. Therefore, we can write the equation:
\[ 72° + 58° + x = 180° \]

4. **Calculate the sum of the known angles**: Add the two given angles together:
\[ 72° + 58° = 130° \]

5. **Set up the equation**: Now substitute the sum back into the equation:
\[ 130° + x = 180° \]

6. **Solve for x**: To find x, subtract 130° from both sides of the equation:
\[ x = 180° - 130° \]

7. **Calculate the value of x**: Perform the subtraction:
\[ x = 50° \]

8. **Conclusion**: The measure of the third angle is 50°.

### Final Answer:
The measure of the third angle of the triangle is **50°**.

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