Question

Se da triunghiul ABC, D apartine (AB), E apartine (AC) si DE||BC . e) Daca AC=14 cm, AD=2,5 cm, DE=4cm si BC=16cm, calculati AE,AB,DB,EC.

Answer 1

Răspuns:

∆ABC≈ ∆DEdeoareceDE ll BC

=>rapoartele de asemănare

AD/AB=AE/AC=DE/BC

2,5/(BD+2,5)=AE/14=4/16=1/4

AE=14/4=7/2cm=3,5cm

BD+2,5=4×2,5=10

BD=10-2,5=7,5cm

AB=7,5+2,5=10cm

EC=14-3,5cm=10,5cm