The Genius of Line

y = mx + h
what does this equation represent. A line? Think again. It gives you only one output, one point on graph. How come it gives you a line.
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This simple equation is a world in itself. m – the coefficient (slope, rate of change, correlation), x- the variable (the input data, the independent variable) and then the h- the y-intercept (bias, the step activation function, decision maker). They can be dynamic at one stage and static at another.
I have no words for the person who came up with this equation… it is beyond Genius.