Question

find the diameter of a circle whose area is 628cm square (use pi-3.14)
plz answer​

Answer 1

Answer:

we know that

area of circle =πr^2

•°• 628 =π r^2

r^2 = 628/π

= 628/3.14

=200

r = 10√2cm

Answer 2

Given : The Area of circle is 628 cm² and $\pi$ = 3.14

Need To Find : The Diameter of Circle.

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❍ Let's Consider Radius of Circle be x cm respectively.

$\frak{\underline{\dag As, \:We\:know\:that:\:}}$

$\star\boxed {\pink{\sf{ Area_{(Circle)} = \pi \times (Radius)^{2} }}}$

⠀⠀⠀⠀⠀⠀$\underline {\bf{\star\:Now \: By \: Substituting \: the \: Given \: Values \::}}$

⠀⠀⠀⠀⠀$:\implies\sf{ 628 = 3.14 \times x^{2} }$

⠀⠀⠀⠀⠀$:\implies\sf{ 628 = 3.14 \times x^{2} }$

⠀⠀⠀⠀⠀$:\implies\sf{ \cancel {\dfrac{628}{3.14}} = x^{2} }$

⠀⠀⠀⠀⠀$:\implies\sf{ 200 = x^{2} }$

⠀⠀⠀⠀⠀$:\implies\sf{ \sqrt{200}= x }$

⠀⠀⠀⠀⠀$\underline {\boxed{\pink{ \mathrm {  x = 14.4\: cm}}}}\:\bf{\bigstar}$

⠀⠀⠀⠀⠀$\therefore {\underline{ \mathrm {Hence,\:  Radius \:of\:Circle \:is\:\bf{14.4\: cm}}}}$

And ,

$\star\boxed {\pink{\sf{ Diameter _{(Circle)} = Radius \times 2}}}$

⠀⠀⠀⠀⠀⠀$\underline {\bf{\star\:Now \: By \: Substituting \: the \: Given \: Values \::}}$

⠀⠀⠀⠀⠀$:\implies\sf{ Diameter_{(Circle )} = 14.4 \: \times 2 }$

⠀⠀⠀⠀⠀$\underline {\boxed{\pink{ \mathrm {  Diameter _{(Circle)} = 28.8\: cm}}}}\:\bf{\bigstar}$

Therefore,

⠀⠀⠀⠀⠀$\therefore {\underline{ \mathrm {  Diameter \:of\:Circle \:is\:\bf{28.8\: cm}}}}$

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