# What is the formula for semiperimeter?

## What is the formula for semiperimeter?

The semi perimeter of a triangle can be calculated if the length of the three sides is given. The formula for the semi perimeter of a triangle is S = (a + b + c)/2, where ‘a’, ‘b’, ‘c’ are the three sides of the triangle.

### What is the in radius of a triangle?

The incircle is the largest circle that can fit inside of a triangle. The radius of this circle is known as the inradius. Inradius can be calculated with the following equation: r=As Where A is the area of the triangle, and s is the semi-perimeter of the triangle, or one-half of the perimeter.

#### How do you find the radius of a triangle?

Calculating the radius Its radius, the inradius (usually denoted by r) is given by r = K/s, where K is the area of the triangle and s is the semiperimeter (a+b+c)/2 (a, b and c being the sides).

**What is the semiperimeter of a right triangle?**

A triangle’s semiperimeter equals the perimeter of its medial triangle. By the triangle inequality, the longest side length of a triangle is less than the semiperimeter.

**What is semiperimeter of rectangle?**

The Semi-Perimeter of a rectangle is equal to half the perimeter, that is width plus height. In squared rectangle theory the semi-perimeter of a squared rectangle is related to the number of spanning trees in the rectangles ‘Smith Diagram’ (a planar graph where edges represent squares).

## How do you find the equation of a circumcircle?

Hint: We can find the radius of the circumcircle by converting the equation into the form ${\left( {x – h} \right)^2} + {\left( {y – k} \right)^2} = {r^2}$. As the circumcircle passes through all the vertices of, we can obtain an equation independent of x and y and eliminate c from the radius.

### How do you find the radii?

radius is always half the length of its diameter. For example, if the diameter is 4 cm, the radius equals 4 cm ÷ 2 = 2 cm.

#### What is Circumradius and Inradius?

Inradius The inradius( r ) of a regular triangle( ABC ) is the radius of the incircle (having center as l), which is the largest circle that will fit inside the triangle. Circumradius: The circumradius( R ) of a triangle is the radius of the circumscribed circle (having center as O) of that triangle.

**Do triangles have a radius?**

Each triangle is Isosceles. This is because two sides are equal (the sides that are a radius). Every side in every triangle is of length r. This is because we have 6 congruent (“equal” in every way) equilateral triangles, and because two sides of every triangle is a radius.

**What is half perimeter?**

From Wikipedia, the free encyclopedia. In geometry, the semiperimeter of a polygon is half its perimeter. Although it has such a simple derivation from the perimeter, the semiperimeter appears frequently enough in formulas for triangles and other figures that it is given a separate name.