Q4 of 186 Page 184

In a ΔABC, AD is the bisector of ∠A.


If AB = 5.6 cm, AC = 4 cm and DC = 3 cm, find BC.

Given: AB = 5.6 cm, AC = 4 cm and DC = 3 cm

Since AD bisects ∠A, we can apply angle-bisector theorem in ∆ABC,



Substituting given values, we get



⇒


⇒ BD = 4.2


Now, BC = BD + DC


⇒ BC = 4.2 + 3 = 7.2


Thus, BC is 7.2 cm.


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