## https://prnt.sc/ikkxw9

Feb 27, 2018

The shaded area = 1085.420262$m {m}^{2}$

#### Explanation:

the area for the big half circle:
Half the Area = $\frac{\pi {r}^{2}}{2}$
so
$\frac{\pi {29}^{2}}{2} = 1321.039711 m {m}^{2}$

small circle area:
Area = $\pi {r}^{2}$
$\pi {5}^{2} = 78.53981634 m {m}^{2}$

now the shaded area will be:
$1321.039711 - \left(78.53981634 \cdot 3\right) =$1085.420262$m {m}^{2}$

• times 3 because you have three white small circles

if I'm wrong someone corrects me, please
thanks :)

Feb 27, 2018

$A = 345.5 \pi$

#### Explanation:

Area of a circle is:

$\pi {r}^{2}$

The area of a semicircle is:

$\frac{1}{2} \pi {r}^{2}$

The radius in respect to diameter is:

$\frac{d}{2}$

The area of the shaded region is the area of the semicircle minus the area of the three white circles.

The area of the semicircle we have here is:

$A = \frac{1}{2} \pi {\left(\frac{58}{2}\right)}^{2}$

$A = \frac{1}{2} \pi {\left(29\right)}^{2}$

$A = \frac{1}{2} \pi 841$

$A = 420.5 \pi$

The area of three white circles is:

$A = 3 \cdot \pi \cdot {5}^{2}$

$A = 3 \cdot \pi \cdot 25$

$A = 75 \cdot \pi$

The area of the shaded region is:

$A = 420.5 \pi - 75 \pi$

$A = 345.5 \pi$