Daabacaaddan, waxaan ka fiirsan doonaa sida loo xisaabiyo wareegga saddex-xagalka iyo falanqaynta tusaalooyinka xallinta dhibaatooyinka.
Qaacidada Wareegga
Wareegga (P) saddex xagal kasta wuxuu la mid yahay wadarta dhererka dhinacyadeeda oo dhan.
P = a + b + c
Wareegga saddexagalka isosceles
Saddex-xagalka isosceles waa saddex xagal oo labadiisa dhinac ay siman yihiin ( aan u soo qaadanno sida b). Dhinac a, oo leh dherer ka duwan dhinacyada, waa saldhigga. Sidaa darteed, wareegtada waxaa loo xisaabin karaa sida soo socota:
P = a + 2b
Wareegga saddexagalka siman
Saddex xagal siman ama midig ayaa loo yaqaan, kaas oo dhammaan dhinacyadu siman yihiin ( aynu u soo qaadanno sidii a). Wareegga shaxanka waxaa loo xisaabiyaa sida soo socota:
P = 3a
Tusaalooyinka hawlaha
Hawsha 1
Soo hel wareegga saddexagalka haddii dhinacyadoodu siman yihiin: 3, 4 iyo 5 cm.
Go'aanka:
Waxaan ku bedelnaa tirooyinka lagu yaqaan xaaladaha dhibaatadu qaacidada oo hel:
P=3cm+4cm+5cm=12cm.
Hawsha 2
Soo hel wareegga saddexagalka isosceles haddii salkiisu yahay 10 cm dhinaciisuna yahay 8 cm.
Go'aanka:
Sida aan ognahay, dhinacyada saddexagalka isosceles waa siman yihiin, sidaas darteed:
P = 10 cm + 2 ⋅ 8 cm = 26 cm.