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One-Step Equations. Tuesday 9/3 Wednesday 9/4 ^^^Write in your Table of Contents Essential Idea: Most operations have an “undo operation.” We can use this to work backwards and solve problems. Warm Up. COMBINE the like terms: 3x 2 + 4x 2 – 5 4y 2 + 9x – 2y 2 -5xy + 3 – 7xy
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One-Step Equations • Tuesday 9/3 • Wednesday 9/4 • ^^^Write in your Table of Contents • Essential Idea: Most operations have an “undo operation.” We can use this to work backwards and solve problems.
Warm Up • COMBINE the like terms: • 3x2+ 4x2– 5 • 4y2+ 9x – 2y2 • -5xy + 3 – 7xy • Why does 3x2 + 4x2 NOT EQUAL 7x4? CST Released Question: Is the statement true? (-2)(8) = (8)(-2) Yes, by the commutative property. Yes, by the associative property. Yes, by the distributive property of multiplication over addition. No, they it is not true.
Today’s Objective • Students will solve one-step equations.
Inverses Work backwards
HOW DO YOU UNDO… Add 5
HOW DO YOU UNDO… Subtract -13
HOW DO YOU UNDO… Multiply by 3
HOW DO YOU UNDO… Multiply by -3
HOW DO YOU UNDO… Divide by 4
CHALLENGE • Picture: • One box weighs ________ Explanation:
CHALLENGE • 3. Picture: • One box weighs ________ Explanation:
Let’s practice TRANSLATING into math…Example 1 PICTURE EQUATION What does x equal?
Your Turn! • Translate each picture into math. • Use the pictures to help you solve for x. • 45 seconds of INDIVIDUAL WORK.
Let’s practice TRANSLATING into math… PICTURE EQUATION What does x equal?
Let’s practice TRANSLATING into math… PICTURE EQUATION What does x equal?
How mathematicians solve this problem… 1 1 1 1 1 1 1 1 1 1 1 x + 11 = 15 1 1 1 1 1 1 1 1 1 1 x - 11 - 11 1 1 1 1 1 x = 4
For your notes… Solving One-Step Equations Draw a line under the equal sign to show balance. Undo addition/subtraction on BOTH sides of the equal sign.
Example 1: PROBLEM: EXPLANATION: x + 7 = 13 UNDO addition on BOTH sides of the equal sign - 7 -7 x = 6
Example 2: PROBLEM: EXPLANATION: -4 + x = 12 UNDO subtraction on both sides of the =. +4 +4 x = 16
Example 3: PROBLEM: EXPLANATION: - 7 = 6 + x UNDO addition on BOTH sides of the equal sign - 6 -6 -13 = x
Assignment • Self-grade Assignment Log • Questions about last assignment • New Assignment: • Solve x-5=24 • Solve 3x=24 • Challenge: Solve 3x-3=24