A reversible statement can be expressed as a biconditional, which in this case means we need to combine both the original statement and its converse. Therefore, we can express the statement as:
If two lines are perpendicular, then they intersect to form four right angles if and only if if two lines intersect to form four right angles, then they are perpendicular.
This biconditional conveys that the two conditions are equivalent: the presence of 90 degree angles at the intersection directly indicates that the lines are perpendicular, and being perpendicular guarantees the formation of those angles. It highlights the relationship between the two geometric properties.