Question extracted from RD sharma of class 10th, Chapter no. 4
Chapter name:- Triangles
Exercise :- 4.2
This is very basic and important questions. And has been asked in several times in exams.
We have ΔABC,
in which D and E are points on the sides AB and AC respectively such that DE || BC.
Also it is given that AD = 2 cm, AB = 6 cm and AC = 9 cm,
Now we have to find AE
learning CBSE maths in effective way.
RD sharma, DHANPAT RAI publication
Given:
Length of side AD = 2 cm, AB = 6 cm and AC = 9 cm
To find: Length of side AC.
Length of DB = AB – AD = 6 – 2 = 4 cm
By using Thales Theorem, we get
AD/BD = AE/CE – equation 1
Now, putting values in equation 1,
2/4 = x/(9 – x)
4x = 18 – 2x
6x = 18
x = 3 cm
∴ AE = 3cm
Therefore, Length of side AE is 3 cm