Number of boxes = y
Height of the stack = x
Slope formula: [tex] \frac{y2-y1}{x2-x1} [/tex]
Choose two points from graph: [tex]1. (8.5, 1)
2.(17, 2) [/tex]
Plug in values (Convert fractions to decimals): [tex] \frac{2 - 1}{17 - 8.5} [/tex]
Solve: [tex] \frac{2-1}{17-8.5} = \frac{1}{8.5} = slope[/tex]
Slope: [tex] \frac{1}{8.5} [/tex]