CurriculumGrade 8Mathematics

Analyzing Graphs Qualitatively

Aligned to 8.F.B.5 — Common Core State Standards for Mathematics.

What this lesson teaches

A graph tells a story: going up means increasing, going down means decreasing, and flat means constant. Steepness shows how fast the change is; straight sections are linear and curved sections are nonlinear.

Worked example

A graph of the water in a tub rises steeply while it fills, stays flat (level) while someone bathes, then drops to zero as it drains. The flat part shows the amount is constant; the steep drop shows a fast decrease.

Practice questions

  1. Describe what a flat horizontal section of a distance-time graph means.
  2. Sketch a graph of a runner speeding up, then resting, then slowing to a stop.
  3. A graph rises, then falls, then rises again — describe a real situation it could model.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

▶ Watch this lesson

En español

Análisis Cualitativo de Gráficas

Una gráfica cuenta una historia: subir significa aumentar, bajar significa disminuir y estar plana significa constante. La inclinación muestra qué tan rápido es el cambio; los tramos rectos son lineales y los tramos curvos son no lineales.

Ejemplo: Una gráfica del agua en una tina sube abruptamente mientras se llena, se mantiene plana (nivelada) mientras alguien se baña, y luego cae a cero al vaciarse. La parte plana muestra que la cantidad es constante; la caída abrupta muestra una disminución rápida.

More Functions lessons

Defining and Comparing Functions8.F.A.1Comparing Functions8.F.A.2Linear vs. Nonlinear Functions8.F.A.3Modeling Linear Relationships8.F.B.4

Teach this lesson today

An AI tutor that guides with questions instead of just giving answers — all K–12 core subjects, every child in the family.

Start free — no card required