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1.) Area of the rectangle :
\(w=4\times r=4\times 3=12 \)
\(h=r+\sqrt{(2r)^2-r^2}+r=2\times 3+3\sqrt{3}=6+3\sqrt{3}\)
Area : \(w\times h=12\times (6+3\sqrt{3})=72+36\sqrt{3}\)
Hope this help ^_^
2.) Area : \(\frac{1}{2}\times AC\times BD\)
\(= \frac{1}{2}\times 4\sqrt{5}\times \sqrt{(5\sqrt{2})^2-(3\sqrt{5})^2}\)
\(= \frac{1}{2}\times 4\sqrt{5}\times \sqrt{5}=10\)