Tse ka Hare
Sehloohong sena, re tla nahana ka tlhaloso ea "triangle" ea bohareng, re thathamise thepa ea eona, 'me re hlahlobe le mehlala ea ho rarolla mathata ho kopanya thepa ea theory.
Tlhaloso ea bokahare ba khutlotharo
E bohareng ke karolo ya mola e hokelang bokatlase ba kgutlotharo le ntlha e bohareng ya lehlakore le lebanang le bethe eo.
- BF ke bokahare bo huleloang ka thoko AC.
- AF = FC
Bohareng ba motheo - ntlha ea mateano ea bohareng le lehlakore la khutlotharo, ka mantsoe a mang, bohareng ba lehlakore lena (ntlha F).
thepa ea bohareng
Thepa 1 (ea mantlha)
Hobane haeba khutlotharo e na le lirotho tse tharo le mahlakore a mararo, joale ho na le li-medians tse tharo, ka ho latellana. Tsohle lia kopana ka nako e le 'ngoeO), e bitsoang centroid or bohare ba kgohedi ya kgutlotharo.
Sebakeng sa mateano a li-medians, e 'ngoe le e' ngoe ea tsona e arotsoe ka karolelano ea 2: 1, ho bala ho tloha holimo. Tseo.:
- AO = 2OE
- BO = 2OF
- CO = 2OD
Thepa 2
Bohareng bo arola kgutlotharo ka dikgutlotharo tse 2 tsa sebaka se lekanang.
S1 =S2
Thepa 3
Li-median tse tharo li arola khutlotharo ka likhutlotharo tse 6 tsa sebaka se lekanang.
S1 =S2 =S3 =S4 =S5 =S6
Thepa 4
Bohareng bo bonyenyane ka ho fetisisa bo lumellana le lehlakore le leholo ka ho fetisisa la khutlotharo, 'me ka tsela e fapaneng.
- AC ke lehlakore le lelelele ka ho fetisisa, kahoo ke la mahareng BF – e kgutshwane ka ho fetisisa.
- AB ke lehlakore le lekgutshwane ka ho fetisisa, ka hona le mahareng CD – e telele ka ho fetisisa.
Thepa 5
Ha re re re tseba mahlakore ohle a kgutlotharo (ha re a nke e le a, b и c).
bolelele ba mahareng mahuleloa ka nqane a, e ka fumanoa ka foromo:
Mehlala ea mesebetsi
Mosebetsi 1
Sebaka sa e 'ngoe ea lipalo tse entsoeng ka lebaka la ho kopana ha li-medians tse tharo ka khutlo-tharo ke 5 cm.2. Fumana sebaka sa kgutlotharo.
tharollo
Ho ea ka thepa ea 3, e boletsoeng ka holimo, ka lebaka la ho kopana ha li-medians tse tharo, li-triangles tse 6 li thehoa, tse lekanang sebakeng. Ka lebaka leo:
S△ = 5 XNUMX cm2 ⋅ 6 = 30 cm2.
Mosebetsi 2
Mahlakore a kgutlotharo ke 6, 8 le 10 cm. Fumana median e huleloang ka lehlakoreng le bolelele ba 6 cm.
tharollo
Ha re sebeliseng mokhoa o fanoeng karolong ea 5:
