Nemo yanki na triangle: dabara da misalai

Bamuda – Wannan siffa ce ta geometric da ta ƙunshi bangarori uku da aka kafa ta hanyar haɗa maki uku akan jirgin da ba ya cikin layi ɗaya.

Gabaɗaya dabara don ƙididdige yanki na triangle

Tushe da tsayi

Yanki (S) na triangle yana daidai da rabin samfurin tushe da tsayinsa.

Tsarin Heron

Don nemo wurin (S) na triangle, kana buƙatar sanin tsawon duk sassansa. Ana la'akari da shi kamar haka:

p - Semi-perimeter na triangle:

Ta bangarorin biyu da kusurwar da ke tsakaninsu

Yankin triangle (S) daidai yake da rabin abin da bangarorinsa biyu suke samu da kuma sinin kwanar da ke tsakaninsu.

Yankin triangle dama

Yanki (S) na siffa yana daidai da rabin abin da aka samo daga kafafunsa.

Yankin triangle isosceles

Yanki (S) ana lissafta ta ta amfani da dabara mai zuwa:

Yankin madaidaicin alwatika

Don nemo yanki na alwatika na yau da kullun (duk bangarorin adadi daidai suke), dole ne ku yi amfani da ɗayan dabarun da ke ƙasa:

Ta tsawon gefen

Ta hanyar tsawo

Misalan ayyuka

Aiki 1

Nemo yanki na alwatika idan ɗaya daga cikin sassansa ya kai 7 cm kuma tsayin da aka zana zuwa gare shi shine 5 cm.

Yanke shawara:

Muna amfani da dabarar da tsayin gefe da tsawo ke ciki:

S = 1/2 ⋅ 7 cm ⋅ 5 cm = 17,5 cm².

Aiki 2

Nemo yanki na alwatika wanda ɓangarorin 3, 4 da 5 cm ne.

1 Magani:

Bari mu yi amfani da dabarar Heron:

Semipermeter (p) = (3 + 4 + 5) / 2 = 6 cm.

A sakamakon haka, S = √6(6-3)(6-4)(6-5) = 6 cm².

2 Magani:

Saboda triangle mai tarnaƙi 3, 4 da 5 yana da rectangular, ana iya ƙididdige yankinsa ta amfani da dabarar da ta dace:

S = 1/2 ⋅ 3 cm ⋅ 4 cm = 6 cm².