Example 3: $m =\frac 1 2 ; b = 1: f(x) = \frac 1 2x + 1$
Each arrow passes through a single point, which is labeled $F =
The point $F$ completely determines the function $f$.
Given a point / number, $x$, on the source line,
there is a unique arrow passing through $F$
meeting the target line at a unique point / number, $ \frac 1 2x +
1$, which corresponds to the linear function's value for the