Overview
This lecture explains how to find the x-intercepts and y-intercepts of a graph or equation.
Finding Intercepts
- Intercepts are points where a graph crosses the x-axis or y-axis.
- The x-intercept(s) occur where the graph crosses the x-axis (y = 0).
- The y-intercept occurs where the graph crosses the y-axis (x = 0).
- To find the x-intercepts, set y = 0 in the equation and solve for x.
- To find the y-intercept, set x = 0 in the equation and solve for y.
Example Process
- For an equation (e.g., y = 2x – 4), set y = 0 to find x-intercepts: 0 = 2x – 4 ⇒ x = 2.
- Set x = 0 in the same equation to find y-intercept: y = 2(0) – 4 ⇒ y = –4.
Key Terms & Definitions
- x-intercept — The value(s) of x where a graph crosses the x-axis (y = 0).
- y-intercept — The value of y where a graph crosses the y-axis (x = 0).
- Intercepts — Points where a graph meets the coordinate axes.
Action Items / Next Steps
- Practice finding x- and y-intercepts for sample equations.
- Review homework problems related to intercepts.