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 & 2.3 Introduction to Algebraic & Geometric Proofs

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

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.

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.

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

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

Assignment Homework: worksheet