Find area of the shaded part in the given diagram

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The discussion focuses on calculating the area of a shaded region using the concepts of semi-circles and sectors. The equations derived indicate relationships between various areas, ultimately leading to the conclusion that the area equals 9. An alternative method suggests leveraging the symmetry of the shaded areas relative to diagonal lines, proposing a simpler solution. The conversation also hints at the possibility of a quarter of the square representing the area. The thread concludes with an invitation for better approaches to the problem.
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Homework Statement
See attached.
Relevant Equations
O level Math
1715334511888.png


1715334531765.png



In my working, i have the following approach;

1715334601803.png


Using area of semi -circle and area of sector concept;

##x +z = \dfrac{9π}{2}##
##x +y = \dfrac{9π}{2}##
##z+p = \dfrac{9π}{2}##

On solving the simultaneous equations,
##⇒x=p##

then,

##x=\dfrac {9π}{4} - \left(\dfrac{1}{2} ×3 ×3\right) = \dfrac{9π-18}{4}##

##⇒ p = \dfrac{9π-18}{4}##

Therefore,

##m+x+p = \dfrac{36-9π}{2} + \dfrac{9π-18}{4} + \dfrac{9π-18}{4}##

##=\dfrac{36-9π}{2} +2\left( \dfrac{9π-18}{4} \right)##

##=\left(\dfrac{36}{2} - 4 .5π+ 4 .5π - 9 \right)= 18-9=9##

Unless there is a better approach. Good day and cheers.
 

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Using symmetry of the individual shaded areas respect to the diagonal lines may be a simpler solution.

0C92EEC6-C5AB-46E3-A16F-247B346BB812.jpeg
 
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chwala said:
Homework Statement: See attached.
Relevant Equations: O level Math

Unless there is a better approach.
An alternative approach:
1715342365041.png


x=x'
m=m'
So, the area is the triangle on the right, i.e., quarter of the square.

EDIT: x-posted with #2.
 
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