Q36 of 40 Page 1

Prove that if a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, then the other two sides are divided in the same ratio.

Let, us consider ABC in which BC || DE



Given – In ABC, BC || DE


To prove - AD : BD = AE : CE


Proof –


For ∆ABC & ADE,


A is common.


As BC || DE


ABC = ADE ………corresponding angles


ABC ADE ………by AA test of similarity


………corresponding sides of similar triangles



……….by dividend



………by invertendo


AD : BD = AE : EC


Hence, if a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, then the other two sides are divided in the same ratio.


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