Answer:
The answer is converse
Step-by-step explanation:
1.Statement : Vertical angles are congruent.
If-then Form : If they are vertical angles, then they are congruent.
Converse : If they are congruent, then they are vertical angles.
Inverse : If they are not vertical angles, then they are not congruent.
Contrapositive : If they are not congruent, then they are not vertical angles.
2.
Statement : A square has four right angles.
If-then Form : If it is a square, then it has a four right angle.
Converse : If it has a four right angle, then it is a square.
Inverse : If it is not a square, then it doesn't have a four right angle.
Contrapositive : If it doesn't have a four right angle, then it is not a square.
3.
Statement : A regular polygon is equilateral
If-then Form : If it is a regular polygon, then it is equilateral.
Converse : If it is equilateral, then it is a regular polygon.
Inverse : If it is not a regular polygon, then it is not an equilateral.
Contrapositive : If it is not an equilateral, then it is not a regular polygon.
