170
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170 degrees
Yes - in the case of triangles in Euclidian geometry. That is, basically triangles in a plane.
If the sum is not 180° you are not in Euclidean space.If the three angles of a triangle add up to more than 180° then you are in a spherical geometry, if the sum is less than 180° it is a hyperbolic space.It must add up to 180 degrees. If not, then it either isn't a triangle, or it is a triangle on some non-planar surface (e.g. a triangle formed by taking three points on a globe).
It is not possible in plane Euclidean geometry, but always true on a convex curved surface such as the face of the Earth.
An obtuse triangle measures 162 degrees.
170 degrees
170
A Plane triangle cannot have parallel sides. A triangle on a sphere, represented in Mercator projection may do so, but that still does not make it so, for that is in spherical geometry. And there are other geometries than Euclidean (plane). Hyperbolic Geometry and Elliptic Geometry are the names of another two. These geometries are consistent within themselves, but some of the theorems in Euclidean geometry have different answers in these alternate geometries.
If a triangle is not scalene, then the triangle does not have three angles with distinct measures.
There are no numbers on that list that could be the sides of a right triangle. Oh, all right. The following is the answer:
A right triangle in geometry is a triangle that has 90 degrees as one of its angles.
Yes - in the case of triangles in Euclidian geometry. That is, basically triangles in a plane.
The proof is pretty simple, but hard to see without the pictures. SO here is a link to the proof with some pics. http://www.apronus.com/geometry/triangle.htm The answer depends on your geometry: In Euclidean geometry, the angle sum is 180 degrees, in Hyperbolic geometry it is less than 180 degrees, and in Elliptical geometry it is greater than 180 degrees.
A+
The altitude of a triangle IS a geometric concept so it intersects geometry in its very existence.
If the sum is not 180° you are not in Euclidean space.If the three angles of a triangle add up to more than 180° then you are in a spherical geometry, if the sum is less than 180° it is a hyperbolic space.It must add up to 180 degrees. If not, then it either isn't a triangle, or it is a triangle on some non-planar surface (e.g. a triangle formed by taking three points on a globe).
The acute triangle will have 3 different acute angle that add up to 180 degrees