| A | B |
|---|
| if-then statement | statement whose form is if hypothesis, then conclusion |
| converse | statement whose form is if conclusion, then hypothesis |
| counterexample | example used to prove that an if-then statement is false |
| biconditional | statement that includes the words "if and only if" |
| complementary angles | two angles whose measures have the sum of 90 degrees |
| supplementary angles | two angles whose measures have the sum of 180 degrees |
| vertical angles | two angles whose sides form two pairs of opposite rays |
| perpendicular lines | two lines lines that intersect to form right angles |
| deductive reasoning | proving statements by reasoning from accepted postulates, definitions, theorems and given information |
