मराठी

Angles A, B, C of a Triangle Abc Are Equal to Each Other. Prove that δAbc is Equilateral.

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प्रश्न

Angles A, B, C of a triangle ABC are equal to each other. Prove that ΔABC is equilateral. 

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उत्तर

Given that angles A,B,C of a triangle ABC equal to each other.
We have to prove that ΔABC is equilateral We have, ∠A = ∠B =∠C
Now, 

[Opposite sides to equal angles are equal] 

and ∠B = ∠C ⇒ AC = AB 

From the above we get 

AB= BC =AC  

⇒ ΔABC is equilateral 

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पाठ 12: Congruent Triangles - Exercise 12.3 [पृष्ठ ४७]

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आर.डी. शर्मा Mathematics [English] Class 9
पाठ 12 Congruent Triangles
Exercise 12.3 | Q 5 | पृष्ठ ४७

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

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ABC is an isosceles triangle with AB = AC and D is a point on BC such that AD ⊥ BC (Figure). To prove that ∠BAD = ∠CAD, a student proceeded as follows:


In ∆ABD and ∆ACD,

AB = AC (Given)

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and ∠ADB = ∠ADC

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[Hint: Recall how ∠B = ∠C is proved when AB = AC].


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