Use a calculator to determine upto two decimal places, the perimeter and the area of the circle in the picture. Circles











5)Use a calculator to determine upto two decimal places, the perimeter and the area of the circle in the picture.



Answer 

BC = 3cm and BD = 6cm


Join CD , thus we obtain a diameter CD



ii. As ∠CBD = 90° (∵ angle in a semi circle is right angle)


Therefore by Pythagoras theorem


BC2 + BD2 = CD2


32 + 62 = CD2


CD2 = 9 + 36 =45


CD = 3√5


Thus, diameter = CD = 3√5


Radius, 

iii)Now change the position of a set of square , and draw another diameter to get the center 



Thus, A is a centre.

Hence the radius 


Ee need to find perimeter of a circle?


We know that,


Perimeter of a circle = 2πr where r = radius



We need to find area of a circle?


We know that,


Area of a circle= π r2 where r= radius 









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