Rectangle Area and Perimeter Calculation

This example demonstrates the calculation of area and perimeter for a rectangle. It involves core mathematical concepts such as area, perimeter, polygon, trigonometric functions, upper and lower sums or Riemann sums, scalene triangles, angles, and similar triangles. The construction uses GeoGebra commands like Polygon and objects including points A, B, C, D, q1, a, b, c, d, and text1. It is suitable for middle school and above students to understand basic properties and calculation methods of geometric shapes.