Grade 7 Workbook — Chapter 11: One- and Two-Step Inequalities
SOL 7.PFA.4 · Companion to Textbook Chapter 11
Each page below is one Canva page. Headings are sized for direct paste: page title as H1, section labels as H2. Figures referenced by filename live in ../figures/. Item numbers match the textbook exactly, so one answer key serves both books. Wherever a graph is asked for, use the blank number lines provided on the page.
PAGE 1 — Chapter opener
Chapter 11 · One- and Two-Step Inequalities
Standard 7.PFA.4
In this chapter you will:
- Solve one- and two-step inequalities in one variable
- Investigate and explain what multiplying or dividing by a negative number does to a solution set
- Graph solution sets on a number line
- Write inequalities for real situations, and write real situations for inequalities
- Decide which numerical values belong to a solution set
- Compare solving inequalities with solving equations
Words to know: inequality · strict inequality · inclusive inequality · solution · solution set · properties of inequality · additive inverse property · multiplicative identity property · reciprocal · reversal rule · boundary value · open circle · closed circle · ray · constraint
Chapter 10 solved two-step equations. Almost every move carries over. Two things change: the answer is usually a whole range of numbers, and multiplying or dividing by a negative number reverses the symbol.
FIGURE: fig2-equation-vs-inequality.png (full width)
PAGE 2 — Four symbols
11.1 What an Inequality Says
Fill in the table.
| Symbol | Read it as | Strict or inclusive? |
|---|---|---|
| is ______________ than | ||
| is ______________ than | ||
| is less than ______ ______________ to | ||
| is greater than ______ ______________ to |
Fill in the blanks.
The symbols and are called ______________ inequalities. The boundary number ______ (is / is not) a solution.
The symbols and are called ______________ inequalities. The boundary number ______ (is / is not) a solution.
The wide end of the symbol always opens toward the ______________ amount.
Words into symbols. Write the symbol that matches each phrase.
| Phrase | Symbol | Boundary included? |
|---|---|---|
| at least | ||
| at most | ||
| more than | ||
| fewer than | ||
| no more than | ||
| exceeds |
PAGE 3 — Solution sets and testing values
The Solution Set
FIGURE: fig1-testing-values.png (full width)
Fill in the blanks.
A ______________ of an inequality is a value that makes the sentence true.
The ______________ ______________ is every value that makes it true.
The equation has ______ solution. The inequality has ______________ many.
To test a value, substitute it into the ______________ inequality, simplify each side, and decide whether the sentence is ______________.
Test each value against . Circle true or false.
| Value | Substituted sentence | True or false? |
|---|---|---|
| ______ | true / false | |
| ______ | true / false | |
| ______ | true / false | |
| ______ | true / false |
Guided practice
Write in words what says. ____________________________________________
Is a solution? ______ Why? ____________________________________________
Test each value in .
: ______ → ______ : ______ → ______ : ______ → ______
Which values from , , , are solutions of ?
: ______ : ______ : ______ : ______
Solutions: ____________________
A backpack may weigh at most 15 pounds. Let = ____________________________
Inequality: ______________ Is a 15-pound backpack allowed? ______
PAGE 4 — Independent practice 11.1
Practice · Lesson 11.1
Write in symbols using .
a) is greater than : ______________ b) is at least 9: ______________
c) is no more than 2.5: ______________ d) is fewer than 30: ______________
Solution or not? Show the substitution.
a) in : ______ → ______
b) in : ______ → ______
c) in : ______ → ______
d) in : ______ → ______
Which values from , , , , are solutions of ? ____________________
Three solutions of , including one that is not an integer and one that is negative:
______, ______, ______
Why does have infinitely many solutions while has exactly one?
Application. A roller coaster requires riders to be at least 48 inches tall.
Let = ____________________ Inequality: ______________
May a rider exactly 48 inches tall ride? ______ Why? ____________________________
Reasoning. Name the one number that is a solution of but not of : ______
Explain: _______________________________________________
Error analysis. Miguel says solves because .
His mistake: _______________________________________________
Is 4 a solution? ______ An inequality with the same left side for which 4 is a solution: ______________
PAGE 5 — Exit ticket 11.1
Exit Ticket · Lesson 11.1
Name: ________________________ Date: ____________
"A class has no more than 28 students." Inequality using : ______________
Which values from , , , are solutions of ? ____________________
Is a solution of ? Substitution: ______ → ______
What is the solution set of an inequality, and why is it usually described rather than listed?
PAGE 6 — The properties of inequality
11.2 Solving One-Step Inequalities
Complete each property.
Addition property. Add the same number to both sides and the comparison stays true in the ______________ direction.
Subtraction property. Subtract the same number from both sides and the direction ______________.
Multiplication property. Multiply both sides by the same ______________ number and the direction stays the same.
Division property. Divide both sides by the same ______________ number and the direction stays the same.
Why the moves are safe.
Adding the same number ______________ both points the same distance along the number line, so which one is on the left ______________ change.
Multiplying by a positive number stretches or shrinks the distance from zero but never moves a point ______________ zero.
The two-sided check. After solving, substitute one value from ______________ the solution set (it should be ______________) and one value from ______________ it (it should be ______________).
Guided practice
Property used: ____________________ Solution: ______________
Inside test: ______ → ______ → ______ Outside test: ______ → ______ → ______
Solution: ______________ Boundary test: ______ → ______
Solution: ______________ Inside test: ______ Outside test: ______
Solution: ______________ Boundary test: ______ → ______
PAGE 7 — Independent practice 11.2
Practice · Lesson 11.2
Solve.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
Solve.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
→ ______________ Rewritten with the variable first: ______________
→ ______________ Three solutions, one negative: ______, ______, ______
→ ______________ Inside test: ______ Outside test: ______
Application. A van carries at most 1{,}500 pounds. Each crate weighs 60 pounds.
Let = ____________________ Inequality: ______________ Solution: ______________
Crates are whole numbers, so the van can carry at most ______ crates.
Reasoning. How is the first move in the same as in , and how do the answers differ?
Error analysis. Nadia solves by dividing by 2 and writes .
Her mistake: ____________________________ Correct solution: ______________
Test : ______ → ______ What this shows: ____________________________
PAGE 8 — Exit ticket 11.2
Exit Ticket · Lesson 11.2
Name: ________________________ Date: ____________
→ ______________ Boundary test: ______ → ______
→ ______________
→ ______________
Property used to solve : ____________________ Solution: ______________
PAGE 9 — The experiment
11.3 The Reversal Rule
FIGURE: fig3-reversal-rule.png (full width)
Run the experiment.
Start with the true statement .
Multiply both sides by : the left becomes ______ and the right becomes ______.
On the number line, is to the ______________ of , so is the ______________ number.
The true statement is ______ . The direction ______________.
Multiplying by ______________ every point across zero, and a reflection turns left into ______________.
Complete the table.
| True statement | Multiply both sides by | Results | New true statement |
|---|---|---|---|
| ______ and ______ | ______ ______ ______ | ||
| ______ and ______ | ______ ______ ______ | ||
| ______ and ______ | ______ ______ ______ | ||
| ______ and ______ | ______ ______ ______ |
PAGE 10 — Sliding is not reflecting
Add a Negative, or Multiply by One?
FIGURE: fig4-shift-versus-flip.png (full width)
Fill in the blanks.
Start with and add to both sides: ______ ______ ______.
Both points slid ______ units to the left, so the direction ______________ (did / did not) change.
Adding a negative ______________ the points. Multiplying by a negative ______________ them across zero.
The reversal rule. Reverse the direction of the symbol only when you ______________ or ______________ both sides by a ______________ number. In every other case the direction ______________.
Reverses or not? Circle one.
| Move | Reverses? |
|---|---|
| add to both sides | yes / no |
| divide both sides by | yes / no |
| subtract 8 from both sides | yes / no |
| multiply both sides by | yes / no |
| multiply both sides by | yes / no |
Guided practice
, multiplied by : ______ ______ ______
, divided by : ______ ______ ______
→ ______________ Test : ______ → ______ Test : ______ → ______
→ ______________ Boundary test: ______ Outside test: ______
PAGE 11 — Independent practice 11.3
Practice · Lesson 11.3
Begin with .
a) Add to both sides: ______ ______ ______
b) Multiply both sides by : ______ ______ ______
c) Which reversed, and why? ____________________________________________
Solve.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
Solve. Watch which ones reverse.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
→ ______________ Inside test: ______ Outside test: ______
Reverses or not, and why?
a) subtract 8 from both sides: ______ because ____________________
b) divide both sides by : ______ because ____________________
c) add to both sides: ______ because ____________________
d) multiply both sides by : ______ because ____________________
Application. A submarine descends 3 meters per second from the surface, so its elevation after seconds is meters.
Inequality for "elevation below meters": ______________
Solution: ______________ In a sentence: ____________________________________________
Reasoning. , multiplied by : ______ ______ ______
Why the direction had to reverse: _______________________________________________
Error analysis. Cleo solves and writes .
Test : ______ → ______ Test : ______ → ______
What the two tests show: ____________________________ Correct solution: ______________
PAGE 12 — Exit ticket 11.3
Exit Ticket · Lesson 11.3
Name: ________________________ Date: ____________
→ ______________
→ ______________
, multiplied by : ______ ______ ______
Why does subtracting a negative not reverse the symbol while dividing by a negative does?
PAGE 13 — Two steps, one question
11.4 Solving Two-Step Inequalities
FIGURE: fig5-two-step-solution.png (full width)
The procedure.
First, name the ______________ and the ______________ term, signs included.
Then undo the ______________ or ______________ on both sides. The direction ______________ changes at this step.
Then undo the ______________ or ______________. Ask: is that number ______________? If yes, ______________ the symbol.
Finally, check with a value from ______________ the solution set and a value from ______________ it.
Where the boundary comes from. The boundary value of the solution set is the solution of the matching ______________.
Guided practice
Step 1: ______ (property: ____________________)
Step 2: ______ (property: ____________________)
Test : ______ → ______ Test : ______ → ______
→ ______ → ______________
Boundary test: ______ → ______ Outside test: ______
→ ______ → ______________
The direction reverses at step ______ because ____________________
Boundary test: ______ → ______
→ ______ → ______________
Test : ______ Test : ______
PAGE 14 — Independent practice 11.4
Practice · Lesson 11.4
Solve.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
Solve. Every part here reverses at some step — mark where.
a) → ______________ b) → ______________
c) → ______________ d) → ______________
→ ______________ (exact)
→ ______________
→ ______________ Variable written first: ______________
Application. A gym charges a $20 joining fee plus $12 per month. Marisol can spend at most $100.
Let = ____________________ Inequality: ______________ Solution: ______________
Whole months she can afford: ______ Check: ______ ______ → ______
Reasoning. → ______________
The direction reverses at the step where ____________________________________
It does not reverse at the other step because ____________________________________
Error analysis. Theo gets to correctly, then writes .
Test in : ______ → ______
What the test shows: ____________________________ Correct solution: ______________
PAGE 15 — Exit ticket 11.4
Exit Ticket · Lesson 11.4
Name: ________________________ Date: ____________
→ ______________
→ ______________
→ ______________
One way solving a two-step inequality is the same as solving a two-step equation:
One way it is different: _______________________________________________
PAGE 16 — Endpoint, circle, direction
11.5 Graphing Solution Sets
FIGURE: fig6-strict-vs-inclusive-endpoint.png (full width)
Fill in the blanks.
Every graph carries three pieces of information: the ______________, the type of ______________, and the ______________ direction.
Use an ______________ circle for or . It says the boundary number ______ (is / is not) a solution.
Use a ______________ circle for or . It says the boundary number ______ (is / is not) a solution.
Shade to the ______________ for or . Shade to the ______________ for or .
FIGURE: fig7-four-solution-shapes.png (full width)
Complete the summary table.
| Inequality | Circle | Shade toward |
|---|---|---|
Variable first. means the same as ______________. Swap the sides and swap the ______________.
PAGE 17 — Guided practice 11.5
Graph It · Lesson 11.5
Use the number lines below. Mark the endpoint, choose an open or closed circle, and shade with an arrowhead.
FIGURE: fig10-blank-number-lines.png (full width)
Endpoint: ______ Circle: ______________ Shade: ______________
Endpoint: ______ Circle: ______________ Shade: ______________
→ ______________ Endpoint: ______ Circle: ______________ Shade: ______________
FIGURE: fig10-blank-number-lines.png (full width)
rewritten with the variable first: ______________
Endpoint: ______ Circle: ______________ Shade: ______________
PAGE 18 — Independent practice 11.5
Practice · Lesson 11.5
For every graphing item, state the endpoint, the circle type, and the shading direction, then draw it on a number line.
FIGURE: fig10-blank-number-lines.png (full width)
Graph each. a) b) c) d)
a) endpoint ______, circle ______________, shade ______________
b) endpoint ______, circle ______________, shade ______________
c) endpoint ______, circle ______________, shade ______________
d) endpoint ______, circle ______________, shade ______________
Solve and graph. a) → ______________ b) → ______________
→ ______________ Endpoint ______, circle ______________, shade ______________
→ ______________ Endpoint ______, circle ______________, shade ______________
A graph shows an open circle at shaded to the right.
Inequality: ______________ Two values in the set: ______, ______ One value not in it: ______
Application. A parking garage admits cars no taller than 6.5 feet.
Let = ____________________ Inequality: ______________
Endpoint ______, circle ______________, shade ______________
Which part of the graph does not describe any real car? ____________________________
Reasoning. Why is the graph of a point but the graph of a ray?
What does the mark at 3 show in each? ____________________________________
Error analysis. Owen graphs with an open circle at shaded right.
Error 1: ____________________ Test value that exposes it: ______
Error 2: ____________________ Test value that exposes it: ______
Correct graph: ____________________________________
PAGE 19 — Exit ticket 11.5
Exit Ticket · Lesson 11.5
Name: ________________________ Date: ____________
FIGURE: fig10-blank-number-lines.png (full width)
Graph . Endpoint ______, circle ______________, shade ______________
→ ______________ Endpoint ______, circle ______________, shade ______________
A graph shows a closed circle at 2 shaded to the left. Inequality: ______________
When do you use an open circle, when a closed circle, and why?
PAGE 20 — From words to symbols
11.6 Inequalities in Context
FIGURE: fig9-whole-number-tickets.png (full width)
The path from a situation to an inequality.
- Read the whole situation.
- Name the unknown, with ______________.
- Find the ______________-unit amount and the ______________ amount.
- Find the limit and choose the ______________.
- Write, solve, and check against the ______________.
Whole-number constraints. When the variable counts objects that cannot be split, the value must be a ______________ number and cannot be ______________.
Algebra gives and tacos are whole, so the answer is at most ______ tacos.
Algebra gives and weeks are whole, so the answer is at least ______ weeks.
The rounding went in ______________ (the same / different) directions, so test the two whole numbers nearest the ______________ instead of memorizing a rule.
Guided practice
Tickets $9 each plus one $6 popcorn; Nia has at most $42.
Let = ____________________ Inequality: ______________ Solution: ______________
Whole tickets: ______
"The temperature , in degrees Celsius, stayed above ." Inequality: ______________
Rosa has $30, spends $4 per book, and wants at least $10 left.
Inequality: ______________ Solution: ______________ Whole books: ______
Write a situation in context for .
Solution: ______________
PAGE 21 — Independent practice 11.6
Practice · Lesson 11.6
Parking: $4 entry plus $2 per hour; Jamal can spend no more than $18.
Inequality: ______________ Solution: ______________
Six more than three times a number is at least 27. Inequality: ______________ Solution: ______________
Five less than twice a number is less than 9. Inequality: ______________ Solution: ______________
Application. An elevator carries at most 1{,}500 pounds. The operator weighs 180 pounds; boxes weigh 55 pounds each.
Let = ____________________ Inequality: ______________ Solution: ______________
Whole boxes: ______
Application. Tacos $2.50 each plus a $1.00 packaging fee; Priya has $14.00.
Inequality: ______________ Solution: ______________ Whole tacos: ______
How you turned the algebra into a number of tacos: ____________________________________
Write a situation in context for , where something decreases.
Solution: ______________
Reasoning. Write a situation in context for .
Solution: ______________ Practical answer: at least ______
Why not "at least 6"? ____________________________________
Error analysis. Bo writes for "shirts $12 each plus a $5 shipping fee, at most $65."
Why it does not match: ____________________________________
Correct inequality: ______________ Solution: ______________
Check the largest whole number: ______ ______ → ______
PAGE 22 — Exit ticket 11.6
Exit Ticket · Lesson 11.6
Name: ________________________ Date: ____________
Taxi: $3 plus $2 per mile; Lena can spend at most $21. Inequality: ______________ Solution: ______________
Four more than five times a number is at most 39. Inequality: ______________ Solution: ______________
Write a situation in context for .
Solution: ______________
When does a context force you to round a fractional answer down to a whole number? Give an example.
PAGE 23 — Review Parts A and B
Chapter 11 Review · Solving
Part A — Properties of inequality (7.PFA.4a)
a) → ______________ b) → ______________
c) → ______________ d) → ______________
a) → ______________ b) → ______________
c) → ______________ d) → ______________
→ ______________
→ ______________ Variable written first: ______________
→ ______________ (exact)
Part B — Multiplying or dividing by a negative (7.PFA.4b)
Begin with .
a) Add : ______ ______ ______ b) Multiply by : ______ ______ ______
c) Which reversed, and why? ____________________________________
a) → ______________ b) → ______________
c) → ______________ d) → ______________
→ ______________ Boundary test: ______ Outside test: ______
Using and a number line, explain why multiplying by a negative reverses the symbol and adding a negative does not.
PAGE 24 — Review Part C
Chapter 11 Review · Graphing (7.PFA.4c)
FIGURE: fig10-blank-number-lines.png (full width)
Endpoint ______, circle ______________, shade ______________
Endpoint ______, circle ______________, shade ______________
→ ______________ Endpoint ______, circle ______________, shade ______________
FIGURE: fig10-blank-number-lines.png (full width)
→ ______________ Endpoint ______, circle ______________, shade ______________
Closed circle at , shaded right. Inequality: ______________ Two solutions: ______, ______
PAGE 25 — Review Parts D and E
Chapter 11 Review · Writing and Creating
Part D — Writing an inequality from a situation (7.PFA.4d)
A checked bag must weigh no more than 50 pounds. Inequality using : ______________
A theater seats at most 250; 40 people are seated.
Inequality for additional people : ______________ Solution: ______________
Bike rental: $6 fee plus $4 per hour; Sam can spend at most $30.
Inequality: ______________ Solution: ______________
Part E — Creating a situation from an inequality (7.PFA.4e)
Situation for :
Solution: ______________
Situation for :
Solution: ______________
Situation for , where something decreases:
Solution: ______________
PAGE 26 — Review Parts F and G
Chapter 11 Review · Context and Solution Sets
Part F — Problems in context (7.PFA.4f)
$150 for pizzas at $13 each plus an $8 delivery fee.
Inequality: ______________ Solution: ______________ Whole pizzas: ______
Mia has $62, earns $14 per lawn, needs at least $160.
Inequality: ______________ Solution: ______________ Whole lawns: ______
A 40-gallon tank drains 6 gallons per minute; it holds more than 10 gallons.
Inequality: ______________ Solution: ______________
Part G — Identifying values in a solution set (7.PFA.4g)
Which of , , , , solve ?
: ______ : ______ : ______ : ______ : ______ Solutions: ____________________
Which of , , , solve ?
: ______ : ______ : ______ : ______ Solutions: ____________________
Three solutions of , one not an integer: ______, ______, ______
Show each works: ____________________________________
PAGE 27 — Review Parts H and I
Chapter 11 Review · Comparing and Mixed
Part H — Inequalities versus equations (7.PFA.4h)
→ ______________ → ______________
How they are related: ____________________ How they differ: ____________________
Two things in common: ____________________________________
Two differences: ____________________________________
Why does have one solution while has infinitely many? How does each graph look?
Part I — Mixed application and reasoning
FIGURE: fig10-blank-number-lines.png (full width)
→ ______________ Endpoint ______, circle ______________, shade ______________
Boundary test: ______ → ______
A student says gives . Test : ______ → ______
What the test shows: ____________________ Correct solution: ______________
An inequality graphed as a closed circle at shaded right: ______________
A different two-step inequality with the same solution set: ______________
Show it: ____________________________________
A van holds at most 44 people; 8 chaperones ride; students sit 4 to a bench.
Inequality for benches : ______________ Solution: ______________ Whole benches: ______
The one number separating from : ______
How the graphs differ: ____________________________________
A situation calling for : ____________________________________
A situation calling for : ____________________________________