Slope and Intercept in Data
Aligned to S-ID.C.7 — Common Core State Standards for Mathematics.
What this lesson teaches
In a line of best fit y = mx + b, the slope m is the predicted change in y for each 1-unit increase in x, and the intercept b is the predicted y when x = 0.
Worked example
A model for plant height is y = 2x + 5, where x is weeks. The slope 2 means the plant grows about 2 cm per week, and the intercept 5 means it started at about 5 cm.
Practice questions
- In y = 0.5x + 10 for savings over weeks, interpret the slope.
- In that same model, interpret the intercept 10.
- A model for temperature is y = −3x + 40. What does the slope −3 mean?
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 lessonEn español
Pendiente e Intersección en los Datos
En una recta de mejor ajuste y = mx + b, la pendiente m es el cambio predicho en y por cada aumento de 1 unidad en x, y la intersección b es el valor predicho de y cuando x = 0.
Ejemplo: Un modelo para la altura de una planta es y = 2x + 5, donde x son semanas. La pendiente 2 significa que la planta crece unos 2 cm por semana, y la intersección 5 significa que empezó en unos 5 cm.
More Statistics & Probability lessons
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