Solved Problem 10 | Cube

$x^2 = 2 \, \text{ unit}^2$
 

Area of hexagon
$A = 6(\frac{1}{2}x^2 \, \sin 60^\circ)$

$A = 6[ \, \frac{1}{2}(2) \, \sin 60^\circ \,]$

$A = 3\sqrt{3} \, \text{ unit}^2$           answer