The sum of the interior angles of a regular heptagon (seven-sided polygon) is:

Options

A. `1080^@`
B. `720^@`
C. `540^@`
D. `900^@`

Answer

To find the sum of the interior angles of a regular heptagon (a seven-sided polygon), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the number of sides (n)**:
A heptagon has 7 sides. Therefore, \( n = 7 \).

2. **Use the formula for the sum of interior angles**:
The formula to calculate the sum of the interior angles of a polygon is:
\[ \text{Sum of interior angles} = (n - 2) \times 180^\circ \]

3. **Substitute the value of n into the formula**:
Plugging in the value of \( n \):
\[ \text{Sum of interior angles} = (7 - 2) \times 180^\circ \]

4. **Perform the subtraction**:
Calculate \( 7 - 2 \):
\[ 7 - 2 = 5 \]

5. **Multiply by 180 degrees**:
Now, multiply the result by 180:
\[ 5 \times 180^\circ = 900^\circ \]

6. **Conclusion**:
Therefore, the sum of the interior angles of a regular heptagon is \( 900^\circ \).

### Final Answer:
The sum of the interior angles of a regular heptagon is \( 900^\circ \).

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