Question

What is the equation in point slope form of the line that passes through (-1, 4) and (3, -4)?

Answer 1

`\bf (\stackrel{x_1}{-1}~,~\stackrel{y_1}{4})\qquad (\stackrel{x_2}{3}~,~\stackrel{y_2}{-4}) \\\\\\ slope = m\implies \cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{-4-4}{3-(-1)}\implies \cfrac{-8}{3+1}\implies \cfrac{-8}{4}\implies -2 \\\\\\ \begin{array}ll \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-4=-2[x-(-1)] \implies y-4=-2(x+1)`