To calculate the slope $m$ of the line passing through two points $(x_1, y_1)$ and $(x_2, y_2)$, we use the slope formula:

$m = \frac{y_2 - y_1}{x_2 - x_1}$

The given points are $(5, 4)$ and $(6, 1)$. Plugging the values into the formula:

$m = \frac{1 - 4}{6 - 5} = \frac{-3}{1} = -3$

Thus, the slope $m$ is $-3$.

Would you like more details or have any questions? Here are five related questions to deepen your understanding:

1. How would the slope change if the coordinates of the points were reversed?
2. What is the slope of a vertical line, and why is it considered undefined?
3. How can you find the slope of a line if given its equation?
4. What is the geometric interpretation of a negative slope?
5. How does the slope of a line relate to its steepness?

Tip: Remember, the slope $m$ represents how much the line rises or falls for every unit it moves horizontally!