Acute and obtuse triangles Acute and obtuse triangles An acute triangle is a triangle with all three angles acute (less than 90°). An obtuse triangle is one with one obtuse angle (greater than 90°) and two acute angles. Since a triangle's angles must sum to 180°, no triangle can have more than one obtuse angle. Acute and obtuse triangles are the two different types of oblique triangles—triangles that are not right triangles because they have no 90° angle. In all triangles, the centroid—the intersection of the medians, each of which connects a vertex with the midpoint of the opposite side—and the incenter—the center of
Platonic realism translated (or transliterated) as "idea," but secondary literature now typically employs the term "form" (or occasionally "kind," usually in discussion of Plato's "Sophist" and "Statesman") to avoid confusion with the English word connoting "thought". Platonic form can be illustrated by contrasting a material triangle with an ideal triangle. The Platonic form is the ideal triangle — a figure with perfectly drawn lines whose angles add to 180 degrees. Any form of triangle that we experience will be an imperfect representation of the ideal triangle. Regardless of how precise your measuring and drawing tools you will never be able to recreate