- Verify that the figure is closed (polygon).
- Verify that the figure is two-dimensional and formed with straight lines only.
- Verify that the figure has exactly three sides.
- Verify that the figure has exactly three vertices.
- Verify that the sum of the angles of the figure is 180 degrees.
- Verify that no two sides are perpendicular to each other
- Verify that the sum of the length of two sides of the traingle should be greater than length of the third side
- Verify that no two angles of triangle have 90 degree and above value.
- Verify the type of traingle is as per the specification, based on its sides – scalene, isosceles or equilateral.
- Verify the type of traingle is as per the specification, based on its angles – acute angle, obtuse angle or right angled triangle.

Nice Article…. Helped me a lot. Thanks for all important questions.