**What do you understand by using the formula of hero or heroon?**

Heron’s formula in geometry is a formula for finding the area of a triangle when all three sides are known. It is also called ‘Hero’s formula’. The sutra is named after Heron of Alexandria.

**Formula of heron**

Δ=√s(s-a)(s-b)(s-c)

s= a+b+c/2

a + b + c / 2 is called half-finite.The half-finite is denoted s.

a + b + c is called the perimeter of triangle ABC.

Where AB = c, BC = a, CA = b

Perimeter of triangle = Sum of the three sides (a + b + c)

**Another method of finding the area of a triangle**

Area of triangle = 1/2 × base × corresponding height.

When AC = b and BD = h where BD⊥AC then

Area of triangle = ½ × bh

**What is Pythagoras theorem?**

If the square of one side of a triangle is equal to the sum of the squares of the other two sides, then which is the right angle in front of the first arm.

**Hypotenuse =** perpendicular ² + base²

Hence, there is a right angle.

**Area of right triangle =** 1/2 × base × corresponding height

**Area of equilateral triangle =** √3 / 4 × side²

**Area of the parallelogram =** base × height.

**Perimeter of parallelogram =** 2 (sum of adjacent sides)

**Area of rhombus =** ½ × (product of diagonals)

**Perimeter of rhombus =** 4 × side

**Area of a quadrilateral =** ½ × (sum of vertices facing the corresponding vertices).

**Area of trapezium =** (sum of parallel sides) × height.