Loading...

Lesson: Geometry - 10

Triangles: Lengths of Sides

[Page 10 of 30]

In an equilateral triangle, all three sides are the same length. In an isosceles triangle, two sides are the same length. An isosceles triangle may be right, obtuse, or acute. In a scalene triangle, none of the sides are the same length. A scalene triangle may be right, obtuse, or acute.

Any side of a triangle cannot be shorter than the difference of the other two sides.

This means that if you subtract the length of any one side from another side, the third side will have to be at least as long as this difference. You can see this yourself by drawing some triangles. Try to make this rule not true — you can't do it!

Any side of a triangle cannot be longer than the sum of the other two sides.

If you add any two sides together, the third side will have to be less than that sum.

Example

Next to display next topic in the chapter.

Test Prep Lessons With Video Lessons and Explained MCQ

Large number of solved practice MCQ with explanations. Video Lessons and 10 Fully explained Grand/Full Tests.