Question

Ons

gr...
Complete the equation of the line through (-8, 8) and (1,-10).
Use exact numbers.

Answer 1

`(\stackrel{x_1}{-8}~,~\stackrel{y_1}{8})\qquad (\stackrel{x_2}{1}~,~\stackrel{y_2}{-10}) \\\\\\ \stackrel{slope}{m}\implies \cfrac{\stackrel{rise} {\stackrel{y_2}{-10}-\stackrel{y1}{8}}}{\underset{run} {\underset{x_2}{1}-\underset{x_1}{(-8)}}} \implies \cfrac{-18}{1 +8} \implies \cfrac{ -18 }{ 9 } \implies - 2`

`\begin{array}c \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{8}=\stackrel{m}{- 2}(x-\stackrel{x_1}{(-8)}) \implies y -8 = - 2 ( x +8) \\\\\\ y-8=-2x-16\implies {\Large \begin{array}{llll} y=-2x-8 \end{array}}`