If one angle of a triangle is equal to the sum of the other two angles, then the triangle is -Maths 9th

If one angle of a triangle is equal to the sum of the other two angles, then the triangle is -Maths 9th
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(d) Let the angles of a AABC be ∠A, ∠B and ∠C. Given, ∠A = ∠B+∠C …(i) InMBC, ∠A+ ∠B+ ∠C-180° [sum of all angles of a triangle is 180°]…(ii) From Eqs. (i) and (ii), ∠A+∠A = 180° ⇒ 2 ∠A = 180° ⇒ 180° /2 ∠A = 90° Hence, the triangle is a right triangle.
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If one angle of a triangle is equal to the sum of the other two angles, then the triangle is -Maths 9th

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