Final answer:
The subject of this question is Mathematics and it is about Linear Equations.
Step-by-step explanation:
In mathematics, the subject you are referring to is called 'Linear Equations'. Linear equations are a type of relationship expressed as algebraic equations of the form y = mx + b, where m and b are constants, x is the independent variable, and y is the dependent variable. The equation represents a straight line on a graph, and the constant m is called the slope, which describes the rate of change between the variables. The constant b is called the y-intercept, which is the point where the line crosses the y-axis.