The approximate area of the regular decagon rounded to the nearest tenth will be 663.4 square units.
Explanation
Radius[tex](r)[/tex] of the regular decagon is 15 units and the length of one side[tex](s)[/tex] is 9.3 units.
Formula for the Area of regular decagon [tex]=\frac{1}{2}\times Perimeter \times Apothem[/tex]
Formula for finding the length of apothem[tex](a)= r*sin(72)[/tex]
So, the length of apothem will be: [tex]15sin(72)[/tex] units
and the perimeter will be: [tex]10s= 10*9.3=93[/tex] units
Thus, the area of the regular decagon [tex]=\frac{1}{2}\times 93 \times 15sin(72)=663.361.... \approx 663.4[/tex] square units.
