The sum of the measures of the interior angles of a polygon with [tex]n[/tex] sides is

A. [tex](n-3) 3600^{\circ}[/tex]
B. [tex](n-3) 180^{\circ}[/tex]
C. [tex](n-2) 90^{\circ}[/tex]
D. [tex](n-2) 180^{\circ}[/tex]
E. [tex](n-2) 360^{\circ}[/tex]



Answer :

To find the sum of the measures of the interior angles of a polygon with [tex]\( n \)[/tex] sides, we use a well-known geometric formula. Here’s a detailed step-by-step explanation:

1. Understand the Formula:
The formula to determine the sum of the interior angles of a polygon with [tex]\( n \)[/tex] sides is given by:
[tex]\[ \text{Sum of interior angles} = (n - 2) \times 180^\circ \][/tex]
This formula arises because a polygon can be divided into [tex]\((n - 2)\)[/tex] triangles, and the sum of the interior angles of each triangle is [tex]\(180^\circ\)[/tex].

2. Explanation:
- A polygon with [tex]\( n \)[/tex] sides can be split into [tex]\((n - 2)\)[/tex] triangles by drawing diagonals from one vertex to all other non-adjacent vertices.
- Each triangle formed in this manner will have angles summing to [tex]\(180^\circ\)[/tex].
- Therefore, the sum of all interior angles of the polygon will be [tex]\((n - 2) \times 180^\circ\)[/tex].

3. Identifying the Correct Option:
Let's now compare the given options to our formula for the sum of interior angles:
[tex]\[ \begin{align*} \text{A.} & \quad (n - 3) \times 3600^\circ \\ \text{B.} & \quad (n - 3) \times 180^\circ \\ \text{C.} & \quad (n - 2) \times 90^\circ \\ \text{D.} & \quad (n - 2) \times 180^\circ \quad (\text{This matches our formula}) \\ \text{E.} & \quad (n - 2) \times 360^\circ \\ \end{align*} \][/tex]

4. Conclusion:
The correct formula for the sum of the interior angles of a polygon with [tex]\( n \)[/tex] sides is [tex]\((n - 2) \times 180^\circ\)[/tex]. Therefore, the correct answer among the options provided is:

[tex]\[ \boxed{(n - 2) \times 180^\circ} \][/tex]

Thus, the answer is option D.