Shaded area

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A square =4*4/2=8

A big ∆=4

A small∆=0.5√2 *√2=1

A shaded =8-(4+1)=3 un²

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Shaded area=[(4/√2)²/2]-[(2/√2)²/2]=3 u²

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x=45+80=125

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3+3=6

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