A biconditional is a single true statement that combines a true conditional and a true converse. We can write a biconditional statement by joining the two parts of each conditional with the phrase if and only if.
A parallelogram is a rectangle if and only if its diagonals are congruent.
If a parallelogram is a rectangle, then its diagonals are congruent.
If the diagonals of a parallelogram are congruent, then the parallelogram is a rectangle.
The second conditional is the converse of the first conditional statement. Also, both conditionals are true, so we can write them as a biconditional. A biconditional is a single true statement that combines a true conditional and a true converse. We can write it by joining the two parts of each conditional with the phrase if and only if.
A parallelogram is a rectangle if and only if its diagonals are congruent.
