All linear functions can be written as [tex]y=mx+q[/tex]
The coefficient m is the slope of the line, and it is the constant rate of change for y, depending on the change of x.
Consider, for example, the function
[tex]y=-2x+3[/tex]
If we start with x=0, we have y=3.
Then, if we increase x by 1 step by step, we have
[tex]\begin{array}{c|c}x&-2x+3\\0&3\\1&1\\2&-1\\3&-3\\4&-5\\\end{array}[/tex]
So, as you can see, as we constantly increase x (by 1), y constantly decreases (by 2, which is the slope of the line: -2)
