The interior angle concept can be extended in a consistent way to crossed polygons such as star polygons by using the concept of directed angles.
32.
Fluckite's mineral crystallography is triclinic meaning it has three axis of different length and three different interior angles that do not equal 90?
33.
One way in which elliptic geometry differs from Euclidean geometry is that the sum of the interior angles of a triangle is greater than 180 degrees.
34.
As the proof only requires the use of Proposition 27 ( the Alternate Interior Angle Theorem ), it is a valid construction in absolute geometry.
35.
By Euclid's exterior angle theorem, any exterior angle of a triangle is greater than either of the interior angles at the opposite vertices:
36.
The interior angle of T * at p'is called the "'comparison angle "'between q and r at p.
37.
Euclid's Proposition 27 states that if a transversal intersects two lines so that alternate interior angles are congruent, then the lines are parallel.
38.
This implies that there are interior angles on the same side of the transversal which are less than two right angles, contradicting the fifth postulate.
39.
A second large brown spot is found beyond the first one and resting on the interior angle and there is a row of submarginal brown streaks.
40.
Therefore, it would make sense for a 180 degree angle to have an interior angle of 180 degrees, and an exterior angle of 0 degrees.
