Question 2.11: Calculate the slope of a line given the following two points......

The slope, m, is calculated using equation (2.8):

m={\frac{\Delta y}{\Delta x}}={\frac{y_{2}  –  y_{1}}{x_{2}  –  x_{1}}}={\frac{-2  –  (1)}{-4  –  (2)}}={\frac{-3}{-6}}={\frac{1}{2}}=0.5

This is exactly the same result that you would obtain if you plotted these points on a graph and measured the slope directly from the graph as height, 3, divided by distance, 6, as illustrated in Figure 2.27. Furthermore, the slope of a straight line is the same when measured between any two points, that is, the slope of a straight line is constant.