NCERT Class 9 Solutions: Triangles (Chapter 7) Exercise 7.1 – Part 1
SideAngleSide congruent
Corresponding Parts of Congruent Triangles
Q1 In quadrilateral , and AB bisects (see Fig). Show that .What can you say about BC and BD
Solution:
Given: In the quadrilateral ABCD, and AB bisects
Prove:
Now,
(Common line)
(Given AB bisects )
(By SideAngleSide congruent rule)
(By Corresponding Parts of Congruent Triangles)
Therefore, BC and BD are of equal lengths.
Q2 ABCD is a quadrilateral in which and (see Fig.). Prove that
Solution:
Give

In

(Common line)

(Given)

(Given)

Therefore, by SideAngleSide congruence condition.


Since,

Therefore by CPCT


Since,

Therefore (by Corresponding Parts of Congruent Triangles)