Question

D and E are points on the sides AB and AC respectively of a ΔABC. In each of the following  cases, determine whether DE║BC or not. 

AD = 5.7cm, DB = 9.5cm, AE = 4.8cm and EC = 8cm. 

 

Answer 1

We have:
`(AD)/(DE)=5.7/9.5=0.6 cm`
`(AE)/(EC)=4.8/8=0.6 cm`
Hence,`(AD)/(DB)=(AE)/(EC)`
Applying the converse of Thales’ theorem,
We conclude that DE || BC