In Following Fig. Abc is an Equilateral Triangle . a Circle is Drawn with Centre a So that Ot Cuts Ab and Ac at M and N Respectively. Prove that Bn = Cm. - Mathematics

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Sum

In following fig. ABC is an equilateral triangle . A circle is drawn with centre A so that ot cuts AB and AC at M and N respectively. Prove that BN = CM.

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Solution

ABC is an equilateral triangle, 

∴ AB = AC 

Also AN = MB (radii of same circle)

⇒ NC = MB 

In Δ BNC and Δ CMB

NC = MB (proved above) 

∠ B = ∠ C  (60° each)

BC = BC  (common)

∴ Δ BNC and Δ CMB  (SAS)

∴ BN = CM   (CPCT)

  Is there an error in this question or solution?
Chapter 17: Circles - Exercise 17.1

APPEARS IN

Frank ICSE Class 10 Mathematics Part 2
Chapter 17 Circles
Exercise 17.1 | Q 9

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