Question

The slope of he line below is 3. Use the coordinates of the labeled point to find a point-slope equation of the line.

Answer 1

First you know that the slope of the line is three. You have the equation : y-y1=m(x-x1) you plug in 3 for m and the coordinate (6,8) for y1 and x1. You then get the equation : y-8=3(x-6) or option c

Answer 2

$\bf (\stackrel{x_1}{6}~,~\stackrel{y_1}{8})~\hspace{10em} slope = m\implies 3 \\\\\\ \begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-8=3(x-6)$