Polygon Construction Compass: Dynamic Classification of Quadrilaterals and Trian

① This interactive GeoGebra example demonstrates a dynamic construction tool where users drag vertices to create and automatically identify various polygons, including quadrilaterals and triangles, along with their special subtypes. ② Core mathematical concepts include classification of quadrilaterals (parallelogram, rectangle, rhombus, square, trapezoid, isosceles trapezoid, kite) and triangles (acute, right, obtuse, isosceles, equilateral, scalene), as well as properties of diagonals (bisecting, congruent, perpendicular) and side parallelism. ③ Construction highlights: using GeoGebra commands Sort, Element, and If to sort side lengths and evaluate conditions; boolean objects like diagBisect, diagCongruent, diagPerpendicular detect diagonal properties; opp1Parallel and opp2Parallel check opposite side parallelism; text objects quadText and triText display the identified type in real time. ④ Suitable for middle school geometry lessons, helping students intuitively understand classification criteria, and useful for teachers creating dynamic courseware or students exploring geometric properties independently.