Use the angle sum of triangles to develop the interior angle sums of regular polygons formula using decomposition. Test the formula by finding the sum of the interior angles of a square.(1 point) Responses The sum of the angles of a square is 360°. The sum of the angles of a square is 360 degrees . The sum of the angles of a square is 1,080°. The sum of the angles of a square is 1,080 degrees . The sum of the angles of a square is 182°. The sum of the angles of a square is 182 degrees . The sum of the angles of a square is 1,440°

1 answer

To derive the formula for the sum of the interior angles of a regular polygon using the angle sum of triangles, we can use the following reasoning:

  1. Understanding the Angles of a Triangle: The sum of the interior angles of a triangle is always \(180^\circ\).

  2. Decomposing a Polygon: A polygon can be divided into triangles. For a regular polygon with \(n\) sides, you can draw diagonals from one vertex to all non-adjacent vertices. This creates \(n-2\) triangles.

  3. Calculating the Sum of Interior Angles: Since each triangle has an angle sum of \(180^\circ\), the total sum of the interior angles of a regular polygon with \(n\) sides can be calculated as follows: \[ \text{Sum of interior angles} = (n - 2) \times 180^\circ \]

Now, let's apply this formula to find the sum of the interior angles of a square (\(n = 4\)):

\[ \text{Sum of interior angles} = (4 - 2) \times 180^\circ = 2 \times 180^\circ = 360^\circ \]

Thus, the sum of the angles of a square is:

The sum of the angles of a square is 360°.

In terms of your possible responses, the correct one is: "The sum of the angles of a square is 360 degrees."