Graphs, Functions, and Models

Finding the Equation of a Line

In Precalculus, understanding how to find the equation of a line given certain information is a foundational skill. This topic involves using points and slopes to write equations and graph lines on the coordinate plane.

• Point-Slope Form: The equation of a line with slope m passing through point is given by:

• Slope-Intercept Form: The equation of a line with slope m and y-intercept b is:

• Graphing a Line: To graph a line, plot the given point and use the slope to find a second point. Draw a straight line through both points.

Example

• Given: A line passes through the point (3, 5) with a slope of 2.

• Equation: Using point-slope form:

• Convert to Slope-Intercept Form:

• Graph: Plot the point (3, 5) and use the slope (rise 2, run 1) to plot a second point. Draw the line through these points.

Additional info: The worksheet image shows a coordinate grid for graphing and a partially written equation, indicating a typical Precalculus exercise on linear equations.