## Perimeter of a Triangle

The perimeter of a triangle equals the sum of the length of its three sides.

 Equilateral Triangle Isosceles Triangle Scalene Triangle      ## Area of a Triangle

The area of a triangle is equal to half its base times its height.

The height of a triangle is each of the perpendicular lines drawn from one vertex to the opposite side (or its extension).  ## Example

Find the area of the triangle:  ### Area of an Equilateral Triangle   ## Example

Calculate the area of an equilateral triangle with a side of 10 cm. ### Area of a Right Triangle

The area of a right triangle equals half the product of the legs.  ## Example

Calculate the area of the right triangle with legs measuring 3 and 4 cm.  ### Semiperimeter

The semiperimeter of a triangle equals half the sum of its sides.

It is denoted with the letter s. ### Heron's Formula

Heron's formula is used to find the area of a triangle knowing the length of all three sides. ## Example

Find the area of the triangle with sides measuring 3, 4 and 5 cm.  ## Circumscribed Circle around a Triangle  R = radius of the circumscribed circle.

## Inscribed Circle in a Triangle  r = radius of the inscribed circle.

s = semiperimeter ## Knowing the Lengths of Two Sides and the Angle between them  Did you like the article?     (1 votes, average: 5.00 out of 5) Loading...

Emma

I am passionate about travelling and currently live and work in Paris. I like to spend my time reading, gardening, running, learning languages and exploring new places.

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