Answer:
y=mx+b.
Explanation:
m represents the slope, or how much the line is increasing/decreasing per every one unit right, and b represents the y-intercept, or the point at which the line crosses the y-axis. y and x don't really represent anything, they just fit in the equation. For example, if a line goes up 2 for every one it goes right, and crosses the y-axis at -3, the equation would be y=2x-3.