Area of a regular hexagon = perimeter x apothem x 1/2
perimeter = 6 x 18 in = 108 in.
Now to calculate the apothem, we have:
Now, using pythagoras theorem:
ap = √ (18² - 9²)
ap = 15.59 in
So, the area of the regular hexagon =
108 x 15.59 x 1/2 = 842 in²