Solving Two-Step Equations
GOAL: I can solve two-step equations with one variable
 Learning Standards  Common Core Standard: 7.EE.1

RED BOOK Reference:

Pages: 142 ─ 146

Practice on page 146,

#23-35 odds.

BLACK BOOK Reference:

Pages: 88 ─ 92

Practice on page 91,

#11-21 odds and

#27-33 odds.

Lesson Vocabulary  
 Equivalent Equations Equations that have the same solutions.
 Addition Property of Equality Adding the same number to both sides of the equation doesn't change the equation.
 Subtraction Property of Equality Subtracting the same number from both sides of the equation doesn't change the equation.
 Isolate Means to get a variable all alone by itself.  You do this using the other properties mentioned in this section.
Once you have the variable all alone by itself, you have the answer to the algebra problem.
 Inverse Operations Inverse operations "undo" other operations.  For example, subtraction undoes addition; multiplication undoes division; and so on.  Every mathematical operation has an inverse operation.
 Multiplication Property of Equality
Multiplying both sides of the equation by the same number doesn't change the equation.
 Division Property of Equality Dividing both sides of the equation by the same number doesn't change the equation.

 Practices (with answers)  

 Solving 2-Step Problems (ver. 1)

 Solving 2-Step Problems (ver. 2)
 Solving 2-Step Problems (ver. 3)


Internet Video Tutorials    



 Time (min: sec)

Solving Two-Step Equations ─16 = (x/4) + 2   3:04
Solving Two-Step Equations
 1.3x ─ 0.7x = 12
5x ─ (3x + 2) = 1
s ─ (3/8)s = (5/6)

Strategies and Content Practice Notes 
Review the 1-step problems, all four varieties, addition, subtraction, multiplication, and division. Make sure students have this prior knowledge.
Remind students that the order of operation is done in reverse for solving algebra problems;
Please Excuse My Dear Aunt Sally is up-side down.
Check for prior knowledge.  Discuss if any have done 2-step problems; if so what do they recall?
Write on the whiteboard "Aunt Sallys Upside Down".
Aunt Sally  (add or subtract first)
MDear (multiply or divide second)
Excuse (exponents come third)
Please (parenthesis come last)
Engage Have students read pages 88 - 92.
Read aloud same with students, emphasize definitions and examples.
Show demonstration videos for Lesson 2-2 (above).

Try this online Algebra Tiles App to practice solving 2-step problems.

After example problems and videos, have students try to solve the Sample Problems below.  After students have had time to complete them, click on the Solutions link and go through the step-by-step process for solving each problem.  Repeat if necessary with additional example problems in the book and re-assess.   

 Sample Problems  Sample Solutions
 5x  8 = 12  Click Here for step-by-step solution.
 3x + 7 = ─ 8  Click Here for step-by-step solution.
 2x  2 = 18  Click Here for step-by-step solution.
 0.5x + 3 = ─ 5  Click Here for step-by-step solution.