Question

formula for area of a circle when you know the diameter

Answer 1

diameter is twice the radius 
so divide the given diametre with 2 u will get radius then go ahead with the formula

Answer 2

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$\bf\Huge\red{\mid{\overline{\underline{ ANSWER }}}\mid }$

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$\Large\fbox{\color{purple}{QUESTION}}$

SURFACE AREA VOLUME FORMULAS

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$\Large\fbox{\color{purple}{ SOLUTION }}$

$\Huge\mathcal\orange{CIRCLE}$

$\Large\mathfrak\red{\implies \: area=\pi \: {r}^{2} }$

$\Large\mathfrak\red{\implies \: area= \: \pi \: (\frac{d}{2} ) ^{2} }$

$\Large\mathfrak\red{\implies \: area= \frac{ \pi \: {d}^{2} }{4} </p><p> }$

$\Large\mathfrak\pink{\implies \: circumference= 2\pi r}$

$\Large\mathfrak\blue{\implies \: semi circle = \frac{ \pi \: {r}^{2} }{2} </p><p> }$

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$\bf\Large\red{ THANKS \: FOR \: YOUR}$

$\bf\Large\red{ QUESTION \: HOPE \: IT }$

$\bf\Large\red{ HELPS }$

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