How to Write Linear Equations from Graphs

Miacademy & MiaPrep Learning Channel

This instructional math video guides students through the process of determining the equation of a line in slope-intercept form ($y = mx + b$) directly from its graph. The narrator, Justin, breaks down the procedure into a logical sequence: first identifying the y-intercept, then calculating the slope using the rise-over-run method between two points, and finally substituting these values into the standard equation variable slots. The video uses visual aids to highlight specific points on the grid and animate the counting of slope units. The content covers four distinct examples that represent the most common scenarios students will encounter: a standard line with a positive slope, a line with a negative slope requiring subtraction in the final equation, a horizontal line with a slope of zero, and a vertical line with an undefined slope. This variety ensures that learners understand not just the basic algorithm, but also the conceptual "edge cases" of zero and undefined slopes, explaining why vertical lines cannot be written in slope-intercept form. This video is highly valuable for Algebra 1 classrooms as it bridges the gap between visual representations (graphs) and algebraic representations (equations). It is particularly useful for visual learners, as it explicitly draws the "rise" and "run" triangles on the screen. Teachers can use this resource to introduce the concept, review before a test, or provide specific remediation on the often-confused horizontal and vertical line equations.