Have you ever drawn a hexagon? If you connect the opposite corners, you see that it divides neatly into six equilateral triangles. So if you can figure out the area of one of those triangles, you will know the area of the hexagon.
Remember that the area of a triangle is half the product of its base and height. The base of the triangle is already given to you, but you have to figure out the height. If you divide the equilateral triangle in half, you'll get two right triangles and you'll split the base in half. Now you know the length of two sides of a right triangle and you can calculate the third. That's the height of the triangle.
Put it all together and you've got your solution.
Hope this helps,
Stephen La Rocque>