Find the angle which is equal to its supplement

Answer

To find the angle which is equal to its supplement, we can follow these steps:

### Step-by-Step Solution:

1. **Define the Angle**:
Let the angle be represented as \( x \).

2. **Determine the Supplement**:
The supplement of an angle is calculated as \( 180^\circ - x \).

3. **Set Up the Equation**:
According to the problem, the angle is equal to its supplement. Therefore, we can write the equation:
\[ x = 180^\circ - x \]

4. **Rearrange the Equation**:
To solve for \( x \), we can add \( x \) to both sides of the equation:
\[ x + x = 180^\circ \]
This simplifies to:
\[ 2x = 180^\circ \]

5. **Solve for \( x \)**:
Now, divide both sides by 2 to find the value of \( x \):
\[ x = \frac{180^\circ}{2} = 90^\circ \]

6. **Conclusion**:
Therefore, the angle which is equal to its supplement is \( 90^\circ \).