A rectangle is a parallelogram with all its inside angles being .
A rhombus is a parallelogram with all its sides are equal, for a rectangle to be a rhombus, its sides must be equal. It becomes a square if this condition is satisfied.
The opposite angles of a rhombus are equal. There are two obtuse angles and two acute angles.
All four sides of a rhombus are equal. The diagonals are not equal, but they intersect at .