Project AMP
Dr. Antonio Quesada – Director, Project AMP
Solving Two Step Equations
This lesson lab was created by Mike Allred, Diane Farmer and Martin Meyer: June 2000 for Project Akron Web
Subject: Pre-Algebra / Algebra
Grade: 7/ 8
Time: 40 minutes
Strand: Algebra
Topic: Solving two-step equations
Objective: Students will solve two-step equations (OPO #15 solving simple number sentences. #16
evaluating algebraic expressions)
Materials: TI Explorer Plus (or equivalent)
Worksheet
Project AMP
Dr. Antonio Quesada – Director, Project AMP
Introduction to Solving Two-step Equations
Overview: For Pre-Algebra and Algebra I students. To develop techniques for solving two-step
equations using TI Explorer Plus (or another calculator with constant operators).
Concepts: Using operations keys to develop a table of values
Determining inverse operations used to solve 2-step equations
Writing and solving 2-step equations given a real world situation
Objectives: Students will solve 2-step equations (OPO #15 Solving simple number sentences
OPO #16 Evaluating algebraic expressions)
Learning Strategies: 1. Review using inverse operations to solve one-step equations
2. Use constant operation keys to develop a series of tables (*see note at end)
3. Determine inverse operations to reverse the input/output of the tables
4. Explain the steps used to solve a 2-step equation:
a) using the calculator
b) using pencil and paper
5. Extension: Solving word problems by writing and solving a 2-step equation
6. Enrichment: Solving other equations using inverse operations.
Assessment: Teacher observation of work
Type II
Evaluation of worksheet Type I; II
Tools and Resources:
TI-Explorer Plus or equivalent
Worksheet
Management: Teacher leads short review. Students work in pairs to complete worksheet. Teacher will
act as facilitator for groups of students. Allowing students to discover concept
techniques and apply knowledge to evaluation and problem-solving.
Do and How:
Review - Distribute worksheets - Complete tables using Explorer Plus - Develop
method for solving 2-step equations - Applying to problem-solving and other equations
Sharing: Students will work in pairs to develop ideas for solving two-step equations and
may share methods that were successful with their classmates.
Results:
Completed worksheets
* Note: To program Op1 and Op2 keys: enter the operation, (i.e. +, -, x,  ) followed by the number
and the Op key. To use the Op keys enter the number and press the Op key desired.
Project AMP
Dr. Antonio Quesada – Director, Project AMP
Solving Two Step Equations Worksheet
Use the Op1 and Op2 keys on the TI-Explorer to fill in the following tables. To program Op1 and Op2
enter the operation followed by the number and Op1 or Op2. Example: to set up Op1 to multiply by 5,
press x, 5, Op1. Now if you enter 3, and press Op1 the result should be 15, that is 3x5.
1. 3x + 2 = y
x
Op1
function
5
x3
3
0
-2
-3
Op1
value
15
Op2
Op2
function value (y)
+2
17





_____________ = x
y
Op1
Op1
Op2
function value function
17
Op2
value (x)
5
What operations were used to fill in the left side of the table? The right side? How are these operations
related?
x
6 y
3
x
Op1
function
9
3
0
-3
-6
2.
____________ = x
Op1
value
Op2
Op2
function value (y)
y





Op1
function
Op1
value
Op2
function
Op2
value (x)
9
Project AMP
x
5 y
2
x
Op1
function
Dr. Antonio Quesada – Director, Project AMP
3.
______________ = x
Op1
value
Op2
Op2
function value (y)
y
Op1
function
Op1
value
Op2
function
Op2
value (x)





Use what you have learned to solve the following equation. 5x -7 = 8.
Extensions: Write an equation for each problem and find the solution.
1. Five children and one adult went to a concert. Adult tickets were $14. The total price for all the
tickets was $59. What was the cost of each child’s ticket?
Equation_______________________________ Solution_______________________________
2. I bought three shirts that had equivalent retail values. I used a $15 gift certificate at the time of
purchase and paid a total of $81.00. How much did each individual shirt cost?
Equation_______________________________ Solution_______________________________
3. Marty ordered three extremely accurate and scientific water-balloon launchers from a mail order
catalog (one for himself and two for his friends). The total price including shipping charges was
$50. If the total shipping cost was $5, how much did each launcher cost?
Equation_______________________________ Solution_______________________________
4. Temperature is usually measured in Celsius (0C) or Fahrenheit (0F). The formula for changing from
Celsius to Fahrenheit is F = 9/5 x C + 32. Use this formula to determine the equivalent Fahrenheit
temperatures, given the following Celsius measurements.
a. 600C = ________________
b. 150C = ___________________
00C = ________________
d. -100C = ___________________
c.
Enrichment: Apply this concept to solving the following.
1.
3x  2
5
4
2.
x  3  12