Can two angles in a triangle be supplementary?It's geography, angles in a triangle.

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alysen31 | Student, Grade 9 | (Level 1) Honors

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In a triangle the three angles add up to 180 degrees. Thus, it is not possible for two angles to be obtuse as well, and only one can also be right. If two angles were to add up to 180 degrees, the third would have the value of 0 degrees, which would not make the triangle possilbe.

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krishna-agrawala | College Teacher | (Level 3) Valedictorian

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Two angles are said to be supplementary if their sum is equal to 180 degrees. It is not possible to for two angles of a triangle to be supplementary. This is because the sum of all the three angles of a triangle is always exactly equal to 180 degrees. Thus if just two angles of a triangle were to be equal to 180 degrees the third angle will have to be zero, And we cannot have an angle equal to zero. An angle equal to zero implies that the two sides of the angle are same. Thus the angle no longer remains an angle. It becomes a straight line. Further when two lines of an angle in a triangle coincide and become one line, the third side of the triangle, which joins the first two line also ceases to exist.

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neela | High School Teacher | (Level 3) Valedictorian

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In any triangle, the sum of the 3 angles is 180 degree or 2 right angles. That is if A,Band C are the vertices of the triange, then

angle A+B+C =180 degree or 2 right angles.

If And B are supplementary, then A+B =180 degree.  So C = 0.

This is a case, when AB is a line segment and  the  expected side from A and  and the line from B wont meet at any finite distance ,or are parallel, or meet at a distance infinitely away at C.. So there is no regular triangle formation with the condition given.

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