two lines that are parallel to each other, will have the same slope.
so if this line is parallel to another with a slope of -5/8, the slope of this line is also -5/8 then. We also know that it passes through -7, 4 and -23, y, let's do some checking.
[tex]\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
% (a,b)
&({{ -7}}\quad ,&{{ 4}})\quad
% (c,d)
&({{ -23}}\quad ,&{{ y}})
\end{array}
\\\\\\
% slope = m
slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ y_2}}-{{ y_1}}}{{{ x_2}}-{{ x_1}}}\implies \cfrac{y-4}{-23-(-7)}\implies \cfrac{y-4}{-23+7}
\\\\\\
\cfrac{y-4}{-16}=\boxed{-\cfrac{5}{8}}\implies 8y-32=80\implies 8y=112
\\\\\\
y=\cfrac{112}{8}\implies y=14[/tex]
