1. **State the problem:** We need to find the sum of the interior angles of a heptagon, which is a polygon with 7 sides. 2. **Formula:** The sum of the interior angles of any polygon with $n$ sides is given by: $$\text{Sum} = 180^\circ \times (n - 2)$$ This formula works because a polygon can be divided into $(n-2)$ triangles, and each triangle has interior angles summing to $180^\circ$. 3. **Apply the formula:** For a heptagon, $n = 7$. $$\text{Sum} = 180^\circ \times (7 - 2)$$ 4. **Simplify inside the parentheses:** $$\text{Sum} = 180^\circ \times 5$$ 5. **Calculate the product:** $$\text{Sum} = 900^\circ$$ 6. **Answer:** The sum of the interior angles of a heptagon is $900^\circ$.