What is the standard form of a linear equation?

The standard form of a linear equation is typically expressed as ax + by = c, where a, b, and c are constants, and x and y are variables. In this format, 'a' and 'b' cannot both be zero, which ensures that the equation represents a linear relationship between x and y. This form is useful in analyzing linear equations, especially for situations like finding intercepts or converting into slope-intercept form.

This format contrasts with other forms, such as y = mx + b, which is the slope-intercept form, emphasizing the slope (m) and y-intercept (b) directly. The option involving y = ax² + bx + c represents a quadratic equation, which is inherently nonlinear due to the squared term. Lastly, the equation y² = ax + b is a nonlinear equation as well, as it features the variable y squared, indicating that it would graph as a parabola rather than a straight line. Therefore, option B accurately represents the standard form of a linear equation.