How can a triangle be classified in two ways?

You can classify a triangle by its sides, or by its angles.

To classify a triangle by its sides:

1- A triangle with three sides that are equal in length is called an equilateral triangle.

2- A triangle with two sides of the same length and one different is called an isosceles triangle. 3- A triangle with no sides of equal length is called a scalene triangle. To classify a triangle by its angles: 1- A triangle with three angles that are greater than 0 and less than 90 degrees is called an acute triangle.

2- A triangle with one angle that is 90 degrees exactly is called a right angle triangle.

3- A triangle with one angle that is greater than 90 degrees is called an obtuse triangle.