Triangle Geometric Shapes

Types of Triangle Geometric Shapes

Types of triangles can be classified by angles and length of sides. Triangles by length of sidesEquilateral Triangles, Isosceles Triangles, and Scalene Triangles. Triangles by anglesRight Triangles, Acute Triangles, Obtuse Triangles, and Oblique Triangles.

Triangles by Length of Sides

Equilateral Triangle

Equilateral triangles have all sides equal length, and all angles equal to 60°. All equilateral triangles have 3 lines of symmetry.

Isoscles Triangle

Isosceles triangles have 2 sides of equal length, and 2 angles are equal. All isosceles triangles have a line of symmetry.

Scalene Triangle

Scalene triangles have no sides of equal length, and no angles are equal.

Triangles by Angles

Acute Triangle

Acute triangles have all angles acute, or three angles<90°.

Right Triangle

Right triangles, or right angled triangles, have one right angle, or one angle=90°.

Obtuse Triangle

Obtuse triangles have one obtuse angle, or an angle>90°. The other two angles are acute (less than 90° ). Oblique - One angle greater than 90°

Oblique Triangle

An oblique triangle is any triangle that is not a right triangle. It could be an acute triangle or obtuse triangle.