Flashcard 13 - Geometry Flashcard Set for the Math Basics

contrapositive

The conditional (If P, then Q) has the same truth value as the contrapositive (If not Q, then not P). Also, the converse (If Q, then P) has the same truth value as the inverse (If not P, then not Q).

Example:
Conditional: If a quadrilateral is a square, then it is a parallelogram. TRUE

Contrapositive: If a quadrilateral is not a parallelogram, then it is not a square. TRUE

Converse: If a quadrilateral is a parallelogram, then it is a square. FALSE (The parallelogram could be a rhombus or rectangle).

Inverse: If a quadrilateral is not a square, then it is not a parallelogram. FALSE (It could be a rectangle, which is a parallelogram).