Is the following definition of perpendicular reversible? if yes, write it as a true biconditional.
two lines that intersect at right angles are perpendicular.
the statement is not reversible.
yes; if two lines intersect at right angles, then they are perpendicular.
yes; if two lines are perpendicular, then they intersect at right angles.
yes; two lines intersect at right angles if (and only if) they are perpendicular.