Area and perimeter formulas are different for irregular shapes compared to regular ones.

1. Irregular Polygons:

• These are shapes with sides and angles that can change in size and measurement.

2. Perimeter:

• To find the perimeter, you just add up the lengths of all the sides.

  For example: $P = a_1 + a_2 + ... + a_n$

• Here, ( n ) stands for the number of sides.

3. Area:

• Figuring out the area can be tricky. There are a couple of ways to do it:

  • Triangulation: This means breaking the shape into triangles to make it easier to calculate the area.

  • Shoelace Theorem: If you know the corners of the shape, called vertices, which are points ((x_1, y_1), \ldots, (x_n, y_n)), the area ( A ) can be found using this formula:

  $A = \frac{1}{2} \left| \sum_{i=1}^{n}(x_iy_{i+1} - y_ix_{i+1}) \right|$

• To use this method, you need the exact coordinates of the vertices.