A rhombus has four congruent sides. (equal) 

A rhombus has opposite sides that are congruent and parallel. 

A rhombus has opposite angles that are congruent. 

The diagonals of a rhombus are perpendicular.
The diagonals cross and make four right angles. 

The diagonals of a rhombus form four congruent interior triangles 

The formula for finding perimeter equals P= 4s s= sides 

The formula for area equals ½ d_{1} * d_{2} d = length of the diagonals 
