Microeconomics

Linear Supply Equation Calculator

Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price.

Runs locally

Inputs and results stay in this browser. Currency symbols are illustrative; use any consistent currency.

Predicted quantity supplied100
Supply intercept (c)-20
Supply slope coefficient (d)6
Price-axis intercept$3.33

Understand Linear supply equation

One idea, three depths

Choose how deeply to explain Linear supply equation

Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Linear supply equation to answer this question: derive a linear supply equation from two observed price-and-quantity points and predict supply at another price? Enter First observed price, First observed quantity, Second observed price, and 2 other inputs; the calculator shows Predicted quantity supplied. For example: If quantity supplied rises from 40 to 70 when price rises from $10 to $15, the equation is Qs = −20 + 6P. At $20, predicted supply is 100 units. The answer tells you Predicted quantity supplied.

Age 15Explain it to a 15-year-oldConnect it to the formula

The observations define a straight-line supply curve. The estimate assumes technology, input costs and other supply conditions remain unchanged. The rule is Qs = c + dP; d = ΔQ ÷ ΔP; c = Q − dP. Its input values are First observed price, First observed quantity, Second observed price, Second observed quantity, Price to predict, and the main result is Predicted quantity supplied. For example: If quantity supplied rises from 40 to 70 when price rises from $10 to $15, the equation is Qs = −20 + 6P. At $20, predicted supply is 100 units.

CollegeExplain it at college levelState the model precisely

This calculator evaluates a microeconomics relationship while holding unmodelled conditions constant. The implemented relation is Qs = c + dP; d = ΔQ ÷ ΔP; c = Q − dP, evaluated from First observed price, First observed quantity, Second observed price, Second observed quantity, Price to predict to produce Predicted quantity supplied. The observations define a straight-line supply curve. The estimate assumes technology, input costs and other supply conditions remain unchanged. The result depends on comparable definitions, units, populations and time periods. It estimates a relationship; it does not establish causation or replace current primary data.

The economic question

Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price.

Why this relationship is useful

The observations define a straight-line supply curve. The estimate assumes technology, input costs and other supply conditions remain unchanged.

Inputs that must be comparable

  • First observed price (minimum 0).
  • First observed quantity (minimum 0).
  • Second observed price (minimum 0).
  • Second observed quantity (minimum 0).
  • Price to predict (minimum 0).

Use one market, firm, population and time period throughout; mixing definitions can make a correctly calculated number economically meaningless.

The model

Qs = c + dP; d = ΔQ ÷ ΔP; c = Q − dP

From inputs to output

The calculator combines First observed price, First observed quantity, Second observed price, Second observed quantity, Price to predict and reportsPredicted quantity supplied together with Supply intercept (c), Supply slope coefficient (d), Price-axis intercept. Change one assumption at a time to identify what actually drives the estimate.

How to read Predicted quantity supplied

Read the sign, magnitude, unit and period together. The result quantifies the relationship in “derive a linear supply equation from two observed price-and-quantity points and predict supply at another price”; it does not by itself prove that one input caused another.

A worked economic example

If quantity supplied rises from 40 to 70 when price rises from $10 to $15, the equation is Qs = −20 + 6P. At $20, predicted supply is 100 units.

Where interpretation can fail

Do not use the result when the input definitions, units or formula assumptions do not match the real situation. This is an educational model, not financial, investment, tax or policy advice; verify material decisions against primary data and professional guidance.

Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Principles of Economics 3e

Read the free OpenStax economics textbook
Cite this book
APA 7
Greenlaw, S. A., Shapiro, D., & MacDonald, D. (2022). Principles of economics 3e. OpenStax. https://openstax.org/books/principles-economics-3e/pages/1-introduction
MLA 9
Greenlaw, Steven A., et al. Principles of Economics 3e. OpenStax, 2022, https://openstax.org/books/principles-economics-3e/pages/1-introduction.
Chicago author-date
Greenlaw, Steven A., David Shapiro, and Daniel MacDonald. 2022. Principles of Economics 3e. Houston, TX: OpenStax. https://openstax.org/books/principles-economics-3e/pages/1-introduction.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Linear Supply Equation Calculator. MW SysArc Tools. https://economics.mwsysarc.com/micro/linear-supply-equation

MLA 9

MW SysArc. “Linear Supply Equation Calculator.” MW SysArc Tools, 21 July 2026, https://economics.mwsysarc.com/micro/linear-supply-equation. Accessed 31 Aug. 2026.

Chicago 17

MW SysArc. “Linear Supply Equation Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://economics.mwsysarc.com/micro/linear-supply-equation.

Harvard

MW SysArc (2026) ‘Linear Supply Equation Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://economics.mwsysarc.com/micro/linear-supply-equation (Accessed: 31 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_linear_supply_2026,
  author = {{MW SysArc}},
  title = {Linear Supply Equation Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://economics.mwsysarc.com/micro/linear-supply-equation},
  note = {Published July 21, 2026; accessed August 31, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Linear Supply Equation Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-31
UR  - https://economics.mwsysarc.com/micro/linear-supply-equation
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Linear supply equation do?

Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price.

How does the Linear supply equation work?

The calculator applies this formula: Qs = c + dP; d = ΔQ ÷ ΔP; c = Q − dP. The observations define a straight-line supply curve. The estimate assumes technology, input costs and other supply conditions remain unchanged.

What can I learn from the Linear supply equation?

It helps you explore the relationship described by this tool: Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price. Change one input at a time to observe how it affects the result.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the result as an estimate or educational aid. Check important financial, business or policy decisions with qualified sources and current data.

Last reviewed . Calculations tested .

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