[tex]slope = m = \cfrac{rise}{run} \implies \cfrac{ f(x_2) - f(x_1)}{ x_2 - x_1}\impliedby \begin{array}{llll} average~rate\\ of~change \end{array}\\\\[-0.35em] \rule{34em}{0.25pt}\\\\ f(x)=2x - 5 \quad \begin{cases} x_1=2\\ x_2=5 \end{cases}\implies \cfrac{f(5)-f(2)}{5-2}\implies \cfrac{[2(5)-5]~~ - ~~[2(2)-5]}{3} \\\\\\ \cfrac{5-(-1)}{3}\implies \cfrac{5+1}{3}\implies 2[/tex]
