In Fig. 6.53, 1 = 2 and 3 = 4.

(i) Is ∆ADC ∆ABC? Why?


(ii) Show that AD = AB and CD = CB.


Given: 1 = 2 and 3 = 4


Formula Used/Theory:-


when 2 angles and side between both the angles are equal in both the triangles then triangles are congruent by ASA congruence criterion


In ∆ADC and ∆ABC


1 = 2 (Given)


3 = 4 (Given)


AC = AC (common)


∆ADC ∆ABC


Hence; both triangles are congruent by ASA congruence


If ∆ADC ∆ABC then;


If triangles are congruent then all 3 sides of triangle are equal to all 3 sides of other triangle


AC = AC


AD = AB


CD = CB


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