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प्रश्न
In a ΔABC, AD is the bisector of ∠A.
If AB = 5.6cm, AC = 4cm and DC = 3cm, find BC.
उत्तर
It is given that AD bisects ∠𝐴.
Applying angle – bisector theorem in Δ ABC, we get:
`(BD)/(DC)=(AB)/(AC)`
⟹`(BD)/3=5.6/4`
⟹`BD=(5.6xx3)/4`
⟹ BD=4.2 cm
Hence, BC = 3+ 4.2 = 7.2 cm
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