Student Goal

I can solve multi-step equations and understand what an inequality means.

Why It Matters

Multi-step equation habits prepare students for 8th grade algebra, functions, and later Math 1 work.

Warm-Up

Warm-Up 1

Solve x + 6 = 14.

Warm-Up 2

Which symbol means greater than?

Warm-Up 3

What is the first step for 2x + 3 = 13?

Short Lesson

Standard Focus

NC.8.EE: Expressions and Equations

Student-Friendly Standard Goal

I can use inverse operations and checking to reason about equations and inequalities.

  • A multi-step equation takes more than one move to solve.
  • Work in an organized order: simplify if needed, undo addition or subtraction, then undo multiplication or division.
  • An inequality compares values. Symbols such as >, <, and >= show more than, less than, or at least.

Guided Examples

Guided Example 1

Solve a Multi-Step Equation

Solve 3x + 4 = 22.

Step 1

3x + 4 = 22

What should we do first?

Guided Example 2

Interpret an Inequality

A student needs at least 18 points to earn a badge. Which inequality represents the points p?

Step 1

at least 18

What does at least mean?

Practice

Problem 1

Solve 2x + 5 = 17.

Problem 2

Solve 4x - 3 = 21.

Problem 3

Which inequality means fewer than 12 books?

Problem 4

True or false: x = 5 is a solution to 3x + 2 = 17.

Problem 5

A student solves 2x + 8 = 20 by dividing by 2 first. What is a better first step?

Reflection

How are you feeling about today's skill?

Optional reflection: What is different about an equation and an inequality?