What is a converse of theorem that is an if-then statement
An example of a converse of a theorem that is an if-then statement is the Converse of the Pythagorean Theorem:
Original Theorem (If-Then Statement): If a triangle is a right triangle, then the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides.
Converse of the Theorem (Converse of an If-Then Statement): If the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides, then the triangle is a right triangle.