In ΔABC, AD is the bisector of ∠BAC, meeting BC at D. If AC = 21, BC = 12 cm and the length of BD is 2 cm less than DC, then the length of side AB is:
Show answer & explanation
Correct answer: C
Explanation
Correct Answer is option 3 i.e. 15 cm
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Understanding |
Application |
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AC = 21, BC = 12 cm and the length of BD is 2 cm less than DC, Suppose CD = x Then, BD = x – 2
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x + x - 2 = 12 ⇒ x = 7 Hence, BD = 7 - 2 = 5 From angle bisector property: AB/AC = BD/DC AB/21 = 5/7 ⇒ AB = 15 cm |
