Interactive Irregular Polygon Calculator

Understanding polygons is much easier when you can see and manipulate them in real time. This interactive tool lets you draw and reshape irregular polygons by dragging their vertices on the canvas. As you explore, the tool automatically:

Calculates each internal angle and displays them in degrees.
Computes the total angle sum and compares it to the theoretical formula (n-2)* 180 degrees
Finds the polygon’s area dynamically as you move the points.

Instructions:

Define your unit system
Enter the number of vertices $n$ (3 to 20) and click "Generate Regular Polygon"
Drag the vertices (red circles) to reshape the polygon as needed
Properties update automatically as you move vertices
Check the angle sum comparison to verify polygon validity

Coordinate System Definition

Unit Type:

Auto-update calculations: (calculations update as you move vertices)

Number of Vertices ($n$):

Coordinate System: Origin at center, 1 unit = 1 cm (50 pixels/unit)

Current vertices: 0

Polygon Properties

Area Formula (Shoelace Formula):

$$\text{Area} = \frac{1}{2} \left| \sum_{i=1}^{n} (x_i y_{i+1} - x_{i+1} y_i) \right|$$

Area: --

Compare the Sum of Angles

Sum of Internal Calculated Angles: --

Expected Sum by Formula:

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

Side	Length

Vertex	Internal Angle	Type

Interactive Irregular Polygon Calculator

Instructions:

Coordinate System Definition

Polygon Properties

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