What is the measure (in degree) of an exterior angle of a regular polygon of 9 sides ?

Options

A. 36
B. 40
C. 30
D. 24

Answer

To find the measure of an exterior angle of a regular polygon with 9 sides, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the number of sides (n)**:
- The polygon has 9 sides, so \( n = 9 \).

2. **Use the formula for the exterior angle**:
- The formula to calculate the measure of an exterior angle of a regular polygon is given by:
\[ \text{Exterior Angle} = \frac{360^\circ}{n} \]

3. **Substitute the value of n into the formula**:
- Plugging in the value of \( n \):
\[ \text{Exterior Angle} = \frac{360^\circ}{9} \]

4. **Calculate the exterior angle**:
- Performing the division:
\[ \text{Exterior Angle} = 40^\circ \]

5. **Final answer**:
- Therefore, the measure of an exterior angle of a regular polygon with 9 sides is \( 40^\circ \).

### Answer:
The measure of an exterior angle of a regular polygon with 9 sides is \( 40^\circ \).

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