To find the sum of the interior angles of a nonagon (a 9-sided polygon), you can use the formula:
\[ \text{Sum of interior angles} = (n - 2) \times 180° \]
where \(n\) is the number of sides.
For a nonagon, \(n = 9\):
\[ \text{Sum of interior angles} = (9 - 2) \times 180° = 7 \times 180° = 1260° \]
Thus, the sum of the interior angles of a nonagon is 1,260 degrees.