#### Answer

If a line bisects a segment, then the line intersects the segment only at its midpoint.
If a line intersects a segment only at its midpoint, then the line bisects the segment.

#### Work Step by Step

The phrases on either side of "if and only if" in a biconditional can be used as the hypothesis and conclusion of a conditional and its converse. Recall that the converse of a conditional switches the hypothesis and conclusion.