check the picture below.
[tex]\bf \stackrel{\textit{area of the semicircle}}{\frac{\pi r^2}{2}}~~~~+~~~~\stackrel{\textit{area of the triangle}}{\frac{1}{2}bh}
\\\\\\
\stackrel{\textit{area of the semicircle}}{\frac{\pi 4^2}{2}}~~~~+~~~~\stackrel{\textit{area of the triangle}}{\frac{1}{2}(12)(8)}
\\\\\\
8\pi +48\qquad \approx\qquad 73.1327412287[/tex]
