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प्रश्न
In a ΔABC, if ∠B = ∠C = 45°, which is the longest side?
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उत्तर
Given that in ΔABC,
∠B=∠C=45°
We have to find longest side
We know that,
Sum of angles in a triangle=180°
⇒∠A+∠B+∠C=180°
⇒∠A+45°+45°=180°
⇒∠A=180°-(45°+45°)=180°-90°=90°
∴ ∠A=90°
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