4.3Modeling with Linear Functions

The graphical-determination example reads k off as −slope and [A]₀ off as the y-intercept of a ln[A] vs. t plot, attaching physical units (h⁻¹) to the slope — this is §4.3's own objective (‘graph and interpret applications of slope-intercept form,’ ‘always attach units to slope and intercept’) rather than §4.2's mechanics of writing a line's equation.

ln k = (−Ea/R)(1/T) + ln A is set beside y = mx + b and the text tells the student the slope equals −Ea/R and the intercept equals ln A — interpreting a real-world slope and intercept in named units is §4.3's objective; §4.2 supplies the line mechanics but not this interpretive step.