Answer:
A = (81 - 20.25π)cm²
P = (18 + 9π)cm
Step-by-step explanation:
Since the answer asks for the exact value, we will keep π as itself to ensure there is no rounding off errors.
Firstly, finding the area A.
> Putting both semicircles together, you will get a full circle. Hence, finding the area only requires you to subtract the circle off the square.
>Also, the radius of the circle is [tex]\frac{9}{2}=4.5[/tex].
Thus,
[tex]A=9^{2} -(\pi *4.5^{2} )\\A= 9^{2}-20.25\pi\\A= (81-20.25\pi)cm^{2}[/tex]
Next, finding the perimeter B.
>Again, combining both arcs of the shaded figure together, we form a circumference of the circle.
Thus,
[tex]P = 2(9) + (2*\pi *4.5)\\=(18+9\pi )cm[/tex]
