--- title: "Demand and Supply as Curves" description: "A demand schedule and a supply schedule become two curves on the same axes: quantity demanded falls as price rises, quantity supplied rises with it. Reading a quantity off a price, and a price off a q" canonical: https://lightmysky.com/learn/civics-and-economics/demand-and-supply-as-curves-mt_FyYrlvzXct source: https://lightmysky.com/learn/civics-and-economics/demand-and-supply-as-curves-mt_FyYrlvzXct.md retrieved: 2026-09-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Demand and Supply as Curves A demand schedule and a supply schedule become two curves on the same axes: quantity demanded falls as price rises, quantity supplied rises with it. Reading a quantity off a price, and a price off a quantity, is the basic move the rest of the model is built from. Subject: Civics & Economics · Area: Economics · Ages 14 to 15 Page: https://lightmysky.com/learn/civics-and-economics/demand-and-supply-as-curves-mt_FyYrlvzXct ## Ready when they can - Plot a demand curve and a supply curve from a table of prices and quantities - State the law of demand and the law of supply and give a reason for each, not just the direction - Read both quantities at a stated price and say which one is larger ## Lesson: Two curves, one market A market starts with two lists. Buyers take 10 apples at 1 coin, 6 at 2 coins and 3 at 3 coins, while sellers offer 2 at 1 coin, 6 at 2 and 10 at 3. You are willing and able to buy at each price on one side, and willing and able to sell on the other. **Example.** Drawn on shared axes, the buyer list slopes down and the seller list slopes up. To read a quantity, pick a price on the price axis, run across to the curve, then down to the quantity axis. At 3 coins the curves read 3 wanted and 10 offered, so supply is larger there. The law of demand says quantity wanted falls as price rises, because some buyers leave or switch to a rival good. The law of supply says quantity offered rises with price, because higher prices draw in higher-cost sellers. Each slope has its reason, not just its direction. **Tip.** Keep the two readings side by side at one price before judging anything. Comparing them is the basic move the rest of the model builds on. **Recap.** Demand slopes down, supply slopes up, and each point pairs one price with one quantity. ## Practice 8 questions on this page, each with its working shown. ## Needs first - [How Markets Work](https://lightmysky.com/learn/civics-and-economics/how-markets-work-mt_IWiQW8Sq2R) - [Scarcity, Opportunity Cost and the Production Frontier](https://lightmysky.com/learn/civics-and-economics/scarcity-opportunity-cost-and-the-production-frontier-mt_p_c7nNzHEw) ## Opens up - [Market Equilibrium, Shortage and Surplus](https://lightmysky.com/learn/civics-and-economics/market-equilibrium-shortage-and-surplus-mt_SarFx2o1IM)