Study of Triangle formulas for various parameters:

If we recall triangle definition, it's a geometric shape with three sides and angles. The name triangle itself indicates that it has 3 angles. There are several triangle formulas for finding the angles. One such triangle formula says that the sum of all 3 angles of a triangle is equal to 180°. Numerically, ∠A + ∠B + ∠C = 180 for A, B & C being the interior angles of a triangle.

Classifying triangles based on the angles:

The sides and angles provides various mechanisms for classifying triangles. On the basis of sides, it is classified in 3 types viz. Equilateral, Isosceles & Scalene. A Equilateral triangle has same length of all 3 sides that makes all angles 60°. Isosceles triangle has 2 sides of same length. Hence the respective opposite angles are also same. Whereas In Scalene triangle, all sides have different length. The figure below makes this things clear.


Triangle Math lets you classify them on the basis of their internal angles viz. Right-Angled, Acute-Angled & Obtuse-Angled triangle. A Right-Angled triangle has one of its angle equal to 90°. A triangle having all of its angles less than 90° is called an Acute-Angled triangle. While a triangle with one of its angle greater than 90° is called Obtuse-Angled triangle as shown below.


Let's find out the Perimeter of a triangle:

Perimeter of a triangle is given by the sum of the lengths of its sides. Hence Perimeter of the below given triangle will be P= a + b + c.


Have a look at different Triangle properties:

The triangle properties & triangle theorems build the basic of study of geometry. One such property is that of triangle inequality. It states that the sum of 2 sides of a triangle is always greater than the 3rd side, i.e. from the above diagram, it's always true that a + b > c, a + c > b & b + c > a.

Area of a triangle is also it's important property. Area = base * height/2. One more property is to find the Volume of triangle prism. It is given by V = base * height * length /2.


More topics in Triangles
Triangles Area of Triangles
Isosceles Triangles Triangle Inequatdty Theorem
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