Classification of triangles
Triangles differentiated on the basis of their sides
Equilateral Triangles:
A triangle with all sides equal to one another is called an equilateral triangle.
Isosceles Triangle:
A triangle with a pair of equal sides is called an isosceles triangle.
Scalene Triangle:
A triangle in which all the sides are of different lengths and no two sides are equal, the triangle is called a scalene triangle.
Triangles differentiated on the basis of their angles.
Acute angled triangle.
A triangle whose all angles are acute is called an acute-angled triangle or simply an acute triangle.
A right triangle has one angle 90°
Right Isosceles Triangle :
Has
a right angle (90°), and also two equal angles
Can you guess what
the equal angles are?
The Obtuse Triangle
The Obtuse Triangle has an obtuse angle (an obtuse angle has more than 90°). In the picture on the left, the shaded angle is the obtuse angle that distinguishes this triangle. Since the total degrees in any triangle is 180°, an obtuse triangle can only have one angle that measures more than 90°.
Interior angles of a triangle
The interior angles are those on the inside of the triangle.
Exterior Angles of a triangle
An exterior angle is formed by extending any side of the triangle.