Which equation represents a linear equation?

The equation that best represents a linear equation is the one in the form ( y = mx + b ), which defines a straight line on a Cartesian plane. In this equation, ( m ) represents the slope of the line, indicating how steep the line is, and ( b ) is the y-intercept, which is the point where the line crosses the y-axis. This form clearly expresses ( y ) as a function of ( x ), and it captures the characteristics of linear relationships, where a change in ( x ) results in a proportional change in ( y ).

Other forms provided, while they may represent linear relationships, do not clearly present ( y ) as the subject of the equation. For example, the equation ( mx + b = y ) can be rearranged to the same form ( y = mx + b ), but it does not immediately show the relationship as clearly. The forms ( x = my + b ) and ( y = mx + c ) are either not in standard form for linear equations or introduce variables that could complicate the interpretation of the linear relationship. Thus, the choice that clearly demonstrates the standard linear equation format is ( y = mx + b ).