1. Bell Work Find the hypothesis and conclusion 1) If the class behaves, then Mr. Liu will give all the students 5 point extra credit Find the converse 2) If the sun shines, then we go on a picnic Find the truth value of conditional and converse “If two angles intersect to form right angles, then they are perpendicular”

2. Chapter 2.2 Biconditionals and Definitions 1.0 Demonstrate understanding by identifying and giving examples of deductive reasoning

3. Vocabulary Biconditional = when a conditional and its converse are true. You write a biconditional by joining the two parts of each conditional with the phrase “if and only if”

4. Example Conditional statement: “If two angles have the same measure, then the angles are congruent” (true) Converse statement: “If two angles are congruent, then the angles have the same measure” (also true) Biconditional: “Two angles have the same measure if and only if the angles are congruent”

5. Try this Conditional statement: “If three points are collinear, then they lie on the same line” Converse statement: “If they lie on the same line, then three points are collinear” Biconditional: “Three points are collinear if and only if they lie on the same line”

6. Do another one! Conditional statement: “If an angle is a straight angle, then its measure is 180 degrees” Converse statement: “If its measure is 180 degrees, then an angle is a straight angle” Biconditional: “An angle is a straight angle if and only if its measure is 180 degrees”

7. Fact You can go from biconditional statement back to its conditional and its converse

8. Example Biconditional: “Two lines are perpendicular if and only if they intersect to form right angles” Conditional statement: “If two lines are perpendicular, then they intersect to form right angles” Converse statement: “If they intersect to form right angles, then two lines are perpendicular”

9. Homework P90 #1, 3, 7, 11, 14, 18-23