For the Rhombus you know that:
The opposite sides are parallel
All sides have equal length
Its diagonals bisect each other in right angles
You can calculate the area of the Rhombus by either mutiplying its whide by its length, and sice its 4 sides are of equal lenght, the area will be equal to the square of one of it's sides (s):
[tex]A=s^2[/tex]
Or using its diagonals (d1 and d2) you can calculate its area as:
[tex]A=\frac{(d_1\cdot d_2)}{2}[/tex]
