A statement written in the if-then form is a conditional statement.
represents the conditional statement
“if p then q”.
Example :
If two angles are adjacent, then they have a common side.
The part of the statement following if is called the hypothesis, and the part following then is called the conclusion.

Example :
Identify the hypothesis and conclusion of the following statement.
A polygon is a pentagon, if it has five sides.
Hypothesis: The polygon has five sides.
Conclusion: It is a pentagon.