[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)= 2(x-2)^2+1\qquad \begin{cases} x_1=-2\\ x_2=4 \end{cases}\implies \cfrac{f(4)-f(-2)}{4-(-2)} \\\\\\ \cfrac{[2(4-2)^2+1]~~ - ~~[2(-2-2)^2+1]}{4+2}\implies \cfrac{[9]~~ - ~~[33]}{6}\implies \cfrac{-24}{6}\implies -4[/tex]
