Find the angle which is four times its complement.

Explanation

To find the angle which is four times its complement, we can follow these steps:

### Step-by-Step Solution:

1. **Define the angle and its complement**:
Let the angle be \( x \). The complement of the angle \( x \) is given by \( 90 - x \).

2. **Set up the equation**:
According to the problem, the angle \( x \) is four times its complement. Therefore, we can write the equation:
\[ x = 4(90 - x) \]

3. **Expand the equation**:
Now, we will expand the right side of the equation:
\[ x = 360 - 4x \]

4. **Rearrange the equation**:
To isolate \( x \), we can add \( 4x \) to both sides:
\[ x + 4x = 360 \]
This simplifies to:
\[ 5x = 360 \]

5. **Solve for \( x \)**:
Now, divide both sides by 5 to find the value of \( x \):
\[ x = \frac{360}{5} = 72 \]

6. **Find the complement**:
The complement of the angle \( x \) can be calculated as:
\[ 90 - x = 90 - 72 = 18 \]

7. **Conclusion**:
The angle which is four times its complement is \( 72 \) degrees.