Isosceles Triangle

In an Isosceles triangle, two sides are equal and the two angles opposite to the sides are also equal. It can be said that any two sides are always congruent. Area of Isosceles triangle is calculated by using the formula for the area of the triangle as discussed above.

Properties of Isosceles Triangle

  • Two sides of the isosceles triangle are always equal
  • Third side is referred to as the base of the triangle and the height is calculated from the base to the opposite vertex
  • Opposite angles corresponding to the two equal sides are also equal to each other.

Triangles in Geometry

Triangles in Geometry: A Triangle is a polygon with three sides and three corners. The corners are also known as vertices, and the sides that connect them are called edges. The interior of a triangle is a two-dimensional region. A triangle is the simplest form of a Polygon.

  • Triangles can be classified based on their angles: Acute-angled, Obtuse-angled, and Right-angled.
  • Triangles can be classified based on their sides: Equilateral, Isosceles, and Scalene.

Triangles are fundamental geometric shapes that play a crucial role in various fields, from mathematics and architecture to engineering and art. In this comprehensive guide, we delve into the world of triangles, uncovering their diverse properties, types, and real-world applications.

Let’s learn more about what are triangles in maths, their definition, types of triangles, formulas, examples, and practice problems in the article.

Table of Content

  • Triangles Definition
  • Triangle Shape
  • Parts of a Triangle
  • Angles in a Triangle
  • Examples of Triangles in Geometry
  • Properties of Triangles
  • Types of Triangles
  • Types of Triangles Based on Sides
  • Equilateral Triangle
    • Properties of Equilateral Triangle
    • Equilateral Triangle Formulas
  • Isosceles Triangle
    • Properties of Isosceles Triangle
  • Scalene Triangle
    • Properties of Scalene Triangle
  • Types of Triangles Based on Angles
    • Acute Angled Triangle
    • Obtuse Angled Triangle
    • Right Angled Triangle
  • Angle Sum Property of a Triangle
  • Triangle – Line of Symmetry
  • Triangle Formulas
    • Perimeter of Triangle
    • Area of a Triangle
  • Area of Triangle Using Heron’s Formula
    • Steps to Find Area Using Herons Formula
  • Congruent Triangles
    • Ways to Prove Triangle Congruence:
    • Properties of Congruent Triangles:
    • Applications of Congruent Triangles:
  • Similar Triangles
    • Properties of Similar Triangles
    • Formula of Similar Triangles
    • Rules of Similar Triangles
  • Applications of Similar Triangles
  • Triangle Class 9
    • Median of Triangle
    • Altitude of Triangle
    • Centroid of Triangle
    • Circumcentre of a Triangle
    • Orthocentre of a Triangle
    • Incentre of a Triangle
  • Fun Facts about Triangles
  • Triangles Solved Examples
  • Triangles in Geometry – Practice Problems
  • Practice Questions on Triangles in Geometry

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Triangle Shape

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Isosceles Triangle

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