[tex]\bf \begin{array}{ccccccccc}
&&x_1&&y_1\\
&&(~ 5 &,& -4)
\end{array}
\\\\\\
% slope = m
slope = m\implies -\cfrac{3}{8}
\\\\\\
\stackrel{\textit{point-slope form}}{y- y_1= m(x- x_1)}\implies y-(-4)=-\cfrac{3}{8}(x-5)
\\\\\\
y+4=-\cfrac{3}{8}x+\cfrac{15}{8}\implies y=-\cfrac{3}{8}x+\cfrac{15}{8}-4\implies
y=-\cfrac{3}{8}x-\cfrac{17}{8}[/tex]