What Is Linear Equation?
A linear equation is any equation where every variable term is raised to the first power (no squares, roots, or products of variables), so its graph is always a straight line. It's typically written in slope-intercept form (y = mx + b), standard form (Ax + By = C), or point-slope form.
Example
y = 3x + 2 is a linear equation and graphs as a straight line. y = x² + 2 is not linear, since x is squared, and it graphs as a curve instead.