Contents
A cikin wannan labarin, za mu yi la'akari da ma'anar tsaka-tsakin triangle, jera kaddarorinsa, da kuma nazarin misalan warware matsalolin don ƙarfafa kayan ka'idar.
Ma'anar tsaka-tsakin triangle
Median yanki ne na layi wanda ke haɗa ƙarshen triangle tare da tsakiyar tsakiyar gefe sabanin wancan.
- BF shine tsaka-tsakin da aka zana zuwa gefe AC.
- AF = FC
Tsakanin tushe - batu na tsaka-tsakin tsaka-tsaki tare da gefen triangle, a wasu kalmomi, tsakiyar wannan gefen (ma'ana). F).
tsaka-tsaki Properties
Dukiya 1 (babban)
Domin idan triangle yana da nisa uku da gefe uku, to akwai tsaka-tsaki guda uku, bi da bi. Dukkansu suna haduwa lokaci gudaO), wanda ake kira centroid or tsakiyar nauyi na triangle.
A wurin tsaka-tsakin tsaka-tsakin, kowannensu an raba shi a cikin rabo na 2: 1, ƙidaya daga sama. Wadanda.:
- AO = 2 OE
- BO = 2 OF
- CO = 2OD
Kadarori 2
Matsakaici yana raba alwatika zuwa triangle 2 na yanki daidai.
S1 = S ba2
Kadarori 3
Matsakaici uku suna raba alwatika zuwa triangle 6 na yanki daidai.
S1 = S ba2 = S ba3 = S ba4 = S ba5 = S ba6
Kadarori 4
Matsakaicin ƙarami ya yi daidai da mafi girman gefen triangle, kuma akasin haka.
- AC shine gefen mafi tsayi, saboda haka tsaka-tsaki BF – mafi guntu.
- AB shi ne mafi guntu gefe, saboda haka matsakaici CD – mafi tsawo.
Kadarori 5
A ce mun san dukkan bangarorin triangle (bari mu dauke su a matsayin a, b и c).
matsakaicin tsayi maja gefe a, ana iya samun ta hanyar dabara:
Misalan ayyuka
Aiki 1
Yankin daya daga cikin alkalumman da aka kafa a sakamakon tsaka-tsakin tsaka-tsakin tsaka-tsaki guda uku a cikin alwatika shine 5 cm.2. Nemo yankin triangle.
Magani
Dangane da dukiya na 3, wanda aka tattauna a sama, sakamakon haɗuwar tsaka-tsakin tsaka-tsakin uku, an kafa triangles 6, daidai a cikin yanki. Sakamakon haka:
S△ = 5 cm ba2 6 = 30 cm2.
Aiki 2
Gefen triangle sune 6, 8 da 10 cm. Nemo tsaka-tsakin da aka zana zuwa gefe tare da tsawon 6 cm.
Magani
Bari mu yi amfani da dabarar da aka bayar a cikin dukiya 5:
