多边形的面积与周长

GeoGebra 命令及参数

1. Polygon(A, B, C, D) → poly1, a, b, c, d
2. Point(yAxis) → E
3. Dilate(A, 4, E) → A'
4. Dilate(B, 4, E) → B'
5. Dilate(C, 4, E) → C'
6. Dilate(D, 4, E) → D'
7. Polygon(A', B', C', D') → poly1', a', b', c', d'
8. PointIn(poly1) → Pointpoly1_1
9. PointIn(poly1') → Pointpoly1'_1
10. Perimeter(poly1) → perimeterpoly1
11. PointIn(poly1) → Pointpoly1
12. Perimeter(poly1') → perimeterpoly1'
13. PointIn(poly1') → Pointpoly1'