Question

please explain it in a rough paper ​

Answer 1

Answer:

This quadrilateral is an square then

area of shaded region = area of square -area of 4 sector

=21×21-90/360×22/7×21/2×21/2

=441-693/8

=441-86.625

=354.375cmsquare

Answer 2

$\huge\underline\mathrm{Answer-}$

$\large{\boxed{\blue{\mathrm{Area\:of\:shaded\:region=94.5\:cm^2}}}}$

$\huge\underline\mathrm{Explanation-}$

In this figure, there are four quadrants in a square,

$\therefore$ Area of the shaded figure = Area of square - 4 ( Area of quadrant )

$\mapsto$ Area of shaded region = (21)² - 4 ( $\dfrac{90}{360}$ × π × ($\dfrac{21}{2}$)² )

$\mapsto$ Area of shaded region = 441 - $\cancel{4}$ ( $\dfrac{1}{\cancel{4}}$ × π × $\dfrac{441}{4}$ )

$\mapsto$ Area of shaded region = 441 - $\dfrac{441}{4}$π

Putting π = 3.14

$\mapsto$ Area of shaded region = 441 - $\dfrac{441}{4}$ ( 3.14 )

$\large{\boxed{\blue{\mathrm{Area\:of\:shaded\:region=94.5\:cm^2}}}}$

$\huge\underline\mathrm{Formula\:used-}$

★ Area of square = (side)²

★ Area of quadrant = $\dfrac{\pi\:r^2}{4}$