Sharp (angle less than 90 °).
Obtuse (angle greater than 90 °).
Expanded (angle equal to 180 °).
Straight (90 ° angle).
and also there are:
Adjacent (these are two corners with one side in common and the sum of the angles is 180 °).
Vertical (an angle whose sides extend each other and have a common vertex).
Internal (corners that are located inside the triangle).
Convex (greater than 180 ° but less than 360 °).
Full (it is 360 °).
Crosswise lying (angles formed at parallel lines, located obliquely from one another).
Corresponding (angles at parallel straight lines correspond to each other).
One-sided (angles with parallel lines lying on one side).
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