Answer:
there is a formula for a hexagon .. it's
Area = 3
/2 *

where length is the length of one side, assuming all sides are equal
Explanation:
3*
/2= 7.348469228.........
since the length is 10... the length squared is 100
then the total area of the hexagon is 734.8469228......
.. what ever they are
if you want to work with some concepts.. you could also say that a hexagon is just a box with the corners cut off and the triangles that are missing are the equilateral right triangles with a hypotenuse of 10 . and since 2 pieces of those triangles make a square.. you can subtract two squares of that size from the bigger box that the hexagon fits into. this is a long way to figure this out but might be good for trigonometry practice :)
it will also be 734.8463288..... see if you can work that out :)