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Graph a linear relationship

About 15 minutes · 3 reading + 12 practice and checks
Time includes reading, practice, and questions. Extra videos or further study are optional.
See this course’s project requirements

A linear-model comparison with tables, graphs, slope and intercept interpretations, a solved intersection and a limitation note.

Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.

What to include

  • Include input/output definitions and bounded domains.
  • Provide checked tables and labeled linear graphs.
  • Interpret rate and starting output with units.
  • Solve an intersection and verify both outputs.
  • Document a capacity-limited model and all changed-case checks.

Review and revise

Use these criteria to check your work and choose what to improve.

  • Method: applies the course-specific rules to the supplied cases with visible intermediate work.
  • Accuracy: results agree with the stated facts, units, boundaries and independent checks.
  • Reasoning: explains why the result follows and identifies a limitation or unresolved question.
  • Transfer: completes changed cases and revises the final project when a relevant assumption changes.
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Before you begin

The idea in everyday life

Original case: V=4+3t for 0≤t≤4; liters versus elapsed minutes.

The idea

A graph connects a relationship to positions on labeled axes. Use input on the horizontal axis, output vertically, and evenly spaced numerical scales. A line segment preserves a bounded continuous domain; discrete allowed inputs may require points rather than every intervening value.

Follow along

Graph a linear relationship — worked practice

A graph connects a relationship to positions on labeled axes. Use input on the horizontal axis, output vertically, and evenly spaced numerical scales. A line segment preserves a bounded continuous domain; discrete allowed inputs may require points rather than every intervening value.

Original case: V=4+3t for 0≤t≤4; liters versus elapsed minutes.

Case information

Paste at A1.

ARecordBGiven
Original caseOriginal case: V=4+3t for 0≤t≤4; liters versus elapsed minutes.

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  1. 1. 1. Label axes

    Name both axes and their units.

    You should see: Horizontal: t/min; vertical: V/L.

  2. 2. 2. Plot checked points

    Calculate and mark t=0,2,4.

    You should see: Points (0,4),(2,10),(4,16).

  3. 3. 3. Choose the display

    Join points only over the allowed continuous time interval.

    You should see: A straight segment from (0,4) to (4,16).

  4. 4. 4. Read a new point

    Use the rule or segment to find V at t=3.

    You should see: V(3)=13 L; it lies between the neighboring plotted values.

Now change one thing

On y=2+4x, what output should the point at x=3 show?

Your work

What to finish

A labeled graph with checked points and a domain-aware segment or point set.

Common mistake

Watch for this

The graph should respect the allowed domain.

How can I tell I understand it?

Plot a new input correctly and avoid implying prohibited intermediate values.

Try 3 questions

Quick knowledge check

Answer all 3 questions. Get at least 2 right and the lesson completes automatically.

Not yet passed

You’ll get an explanation for each answer. Signed in? Your results save to your account.

1Which point lies on y=5+2x?
2Why must tick spacing represent equal numerical increments?
3A model input is the whole number of teams. What display avoids implying half-teams exist?
0 of 3 answeredApply the lesson to a short question, then review the explanation.
4
Finish this lesson

Pass the check. We’ll save the progress.

Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.

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Sources and further reading

Explore the references behind this lesson.

OpenStax: linear functions
Source & access notes · checked 2026-10-01

Web open/search showed the official page, its topic heading and relevant concept description. This is a content/source check, not a provider endorsement. Exact topic chapters were opened in web result turn 325view 0–14.

Access: Official page retrieved with the web reader on 2026-10-01; interactive tools and videos were not certified by retrieval.

Reuse: Original fictional teaching cases, calculations, questions and examples; link and short factual paraphrase only. No copied source exercises or illustrations.

OpenStax: modeling with linear functions
Source & access notes · checked 2026-10-01

Web open/search showed the official page, its topic heading and relevant concept description. This is a content/source check, not a provider endorsement.

Access: Official page retrieved with the web reader on 2026-10-01; interactive tools and videos were not certified by retrieval.

Reuse: Original fictional teaching cases, calculations, questions and examples; link and short factual paraphrase only. No copied source exercises or illustrations.

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