Mensuration for a Rhombus: Area, Perimeter, Diagonals, Circumcircle
The area of a Rhombus = product of diagonals/2 = (Square of side x sine of base angle) = base x height
Perimeter of a rhombus = 4 * side
The diagonals of a rhombus are not equal unless it is a square.
A square is a special case of a rhombus in which all angles are right angles.