Question 357229
Each side of the hexagon is 9cm. The regular hexagon can be divided into 6 congruent equilateral triangles with a common vertex at the center of the hexagon. Each triangle has height {{{9sqrt(3)/2}}}.  Therefore each triangle has area {{{(1/2)b*h = (1/2)*9*(9sqrt(3)/2)=(81sqrt(3)/4) }}}.  Therefore area of the hexagon is {{{6*(81sqrt(3)/4) = 243sqrt(3)/2}}}sq.cm.