Question
Find the radius of a circle, if its area is:
$4\pi\text{cm}^2$
$4\pi\text{cm}^2$
✓
Answer
Let the radius of the circle be r cm.
$\therefore$ Area of the circle (A) $=4\pi\text{cm}^2$
$\Rightarrow4\pi=\pi\times(\text{r})^2\text{cm}^2$
$\Rightarrow\text{r}^2=\Big(\frac{4\pi}{\pi}\Big)=4$
$\Rightarrow\text{r}=2\text{cm}$
$\therefore$ Area of the circle (A) $=4\pi\text{cm}^2$
$\Rightarrow4\pi=\pi\times(\text{r})^2\text{cm}^2$
$\Rightarrow\text{r}^2=\Big(\frac{4\pi}{\pi}\Big)=4$
$\Rightarrow\text{r}=2\text{cm}$
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