A rhombus is a parallelogram with four congruent sides. To write this as a true biconditional, we can express it in two different ways. ;
A rhombus can be defined using biconditionals in two ways: 1) A quadrilateral is a rhombus if and only if it is a parallelogram with four congruent sides, and 2) A parallelogram is a rhombus if and only if it has four congruent sides. These statements establish the logical equivalence of the conditions. Both forms effectively present the same relationship regarding rhombuses and parallelograms.
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