Area of semi circle formula

Learn and know the formula by which we can find the area of semi circle. If we observe this formula clearly we can find out some interesting relation between areas of circle and semi circle. Knowing that relation makes us easy to remember the formula. Area of circle formula if already studied then learning the area of semi circle formula is very much easy. In semi circle, Semi meaning is half so half of circle will be a semi circle. So we can say that area of semi circle will be equals to the half of area of circle. By this, we can conclude that any one of the formulae out of 2 i.e. area of semi circle or area of circle if you learn then writing the other formula will be easy.

The formula used to find area of semi circle:

In order to find the area of semi circle use the below given formula.

A = ½ × π × r2  where π = 22/7 (or) we can also take π as 3.14 and “r” is the radius of the given semi circle. Example:

If the radius of semi circle is 14 cm then find the area of semi circle.

Solution:

Given

As we know that

A  =  ½ × π × r2

= ½ × 22/7 × 142

= 308 cm2

Therefore, area = 308 cm2

The area of semi circle is given as 77 m2 then find its radius.

Solution:

Given

A = 77 m2

½ × π ×r2  = 77

½ × 22/7 × r2 = 77

r2 = 77 x 2 x 7/22

r2  = 49

r2 = 72

r = 7

Therefore, radius of semi circle is 7 m.

My suggestion is to remember the area of circle formula with that you can write area of semi circle formula without any mistakes. 