1. Do this NOW! Turn in “get to know you” sheet to middle tray
Grab a matching warmup from the podium and DO IT!

2. 2.2 & 2.3 Introduction to Algebraic & Geometric Proofs

3. Notes- add justifications
If a = b, then a + c = b + c If a = b, then a - c = b - c If a = b, then ac = bc If a = b and c ≠ 0, then 𝑎 𝑐 = 𝑏 𝑐 a = a If a = b, then b = a If a = b and b = c, then a = c If a = b, then b can be substituted into a in any expression a(b + c) = ab + ac

4. Types of Proof Paragraph Proofs Flow Chart Proofs Two Column Proofs
Examples in section 2.4
Flow Chart Proofs
Two Column Proofs
This third example is the most commonly used type of proof. We will focus on this type of proof in class.

5. Two Column Proofs Ask Dr. Math is a great place to start.
Statements
In this column we write the logical steps that lead us to the end result.
Reasons
For each statement, we must use a postulate or theorem that supports the statement.

6. Algebraic Proof:
Given: 1 3 𝑥−4=−2
Prove: x = 6

7. Algebraic proof:
Given: − 𝑥−1 +3𝑥=6𝑥−7
Prove: x = 2

8. Assignment
Homework: worksheet