# Maximum and minimum triangle angle sum in non-euclidian geometry

Discussion in 'Geometry and Trigonometry' started by Dheglen, Mar 15, 2022.

1. ### Dheglen

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So, I called my mother and told her that I was trying to construct a triangle with two right angles, and she said "that it's not possible". I said "yes it is", she said "no it isn't" etc...

Anyway, is the maximum angle sum 90 * 3 = 270 degrees, and the minimum close to zero?

Dheglen, Mar 15, 2022
2. ### MathLover1

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Can a triangle have two right angles? The answer is “NO” in Euclidian Geometry., a triangle can never have two right angles. Reason: Sum of the three interior angles of a triangle must be 180 degrees.

but spherical geometry you can have two or even three :

MathLover1, Mar 15, 2022
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3. ### Dheglen

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And an angle can't be 0 degrees?

Dheglen, Mar 16, 2022
4. ### MathLover1

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in Euclidian Geometry
The key reason that triangles cannot have angles which measure is that such a figure would necessarily be 3 points on a straight line, and such a figure is not a triangle.

MathLover1, Mar 16, 2022
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5. ### nycmathguy

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This question should be asked in the Other Advanced Math forum. The Geometry and Trigonometry forum is more for high school and undergraduate mathematics.

nycmathguy, Mar 16, 2022
6. ### nycmathguy

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Is this not geometry beyond the high school and undergraduate level of mathematics? This question should be posted in the Other Advanced Math forum. Agree?

nycmathguy, Mar 16, 2022
7. ### Dheglen

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Does it have to have an area > 0 to be a triangle?

Dheglen, Mar 16, 2022

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