To calculate the total of the interior angles of a heptagon (7-sided polygon), we use the given formula:

$T = 180^\circ \times (n - 2)$

where $T$ is the total sum of the interior angles, and $n$ is the number of sides of the polygon. For a heptagon, $n = 7$.

Substitute $n = 7$ into the formula:

$T = 180^\circ \times (7 - 2)$ $T = 180^\circ \times 5$ $T = 900^\circ$

Thus, the total sum of the interior angles of the heptagon is 900°.

Would you like more details or have any questions?

Here are 5 related questions for further practice:

1. What is the sum of the interior angles of a hexagon (6-sided polygon)?
2. How do you calculate the measure of one interior angle in a regular polygon?
3. What is the total of the exterior angles of any polygon?
4. What is the relationship between the number of sides of a polygon and its interior angles?
5. How do the interior and exterior angles of a polygon add up at each vertex?

Tip: The sum of the exterior angles of any polygon is always 360°, regardless of the number of sides!