Okuqukethwe
Kulolu shicilelo, sizocubungula incazelo kanye nezakhiwo eziyinhloko zemigqa emaphakathi ye-convex quadrilateral mayelana nephoyinti labo lokuhlangana, ubudlelwano namadiagonal, njll.
Qaphela: Ngokulandelayo, sizocubungula isibalo se-convex kuphela.
Ukunqunywa komugqa omaphakathi we-quadrilateral
Ingxenye ehlanganisa amaphoyinti aphakathi ezinhlangothini eziphambene ze-quadrilateral (okungukuthi, ukungawahlanganisi) ibizwa ngokuthi umugqa ophakathi.
- EF – umugqa ophakathi oxhuma amaphoyinti aphakathi AB и I-CD; AE=EB, CF=FD.
- GH – umugqa omaphakathi ohlukanisa amaphoyinti BC и AD; BG=GC, AH=HD.
Izici zomugqa omaphakathi we-quadrilateral
Impahla 1
Imigqa emaphakathi ye-quadrilateral intersect futhi ihlukaniswe kabili endaweni yomgwaqo.
- EF и GH (imigqa ephakathi) nqamula iphuzu O;
- EO=KW, HAMBA=OH.
Qaphela: Point O is i-centroid (noma i-barycenter) i-quadrilateral.
Impahla 2
Iphuzu lokuphambana kwemigqa emaphakathi ye-quadrilateral indawo emaphakathi yengxenye exhuma amaphoyinti aphakathi kwama-diagonal ayo.
- K – maphakathi diagonal AC;
- L – maphakathi diagonal BD;
- KL udlula iphuzu O, ukuxhuma K и L.
Impahla 3
Amaphoyinti aphakathi ezinhlangothini ze-quadrilateral yizimo zepharalelogramu ebizwa ngokuthi I-Parallelogram ye-Varignon.
Isikhungo sepharalelogramu esakhiwe ngale ndlela kanye nephuzu lokuphambana kwama-diagonals ayo indawo ephakathi nendawo ye-quadrilateral yasekuqaleni, okungukuthi indawo yabo yokuhlangana. O.
Qaphela: Indawo yepharalelogramu iyingxenye yendawo ye-quadrilateral.
Impahla 4
Uma ama-engeli phakathi kwama-diagonal we-quadrilateral kanye nomugqa ophakathi nendawo elingana, khona-ke ama-diagonal anobude obufanayo.
- EF - umugqa ophakathi;
- AC и BD - ama-diagonal;
- ∠ELC = ∠BMF = a, Ngenxa yalokho AC=BD.
Impahla 5
Umugqa omaphakathi we-quadrilateral ungaphansi noma ulingana nengxenye yesamba sezinhlangothi zayo ezingaphambanisi (inqobo nje uma lezi zinhlangothi zihambisana).
EF – umugqa ophakathi nendawo ongahlangani nezinhlangothi AD и BC.
Ngamanye amazwi, umugqa omaphakathi we-quadrilateral ulingana nengxenye yesamba sezinhlangothi ezingaphambanisi uma futhi kuphela uma i-quadrilateral enikeziwe iyi-trapezoid. Kulesi simo, izinhlangothi ezicatshangelwayo ziyizisekelo zesibalo.
Impahla 6
Kuvekhtha yomugqa omaphakathi we-arbitrary quadrilateral, ukulingana okulandelayo kubamba:
