[tex]\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
% (a,b)
&({{ 2}}\quad ,&{{ 2}})\quad
% (c,d)
&({{ 5}}\quad ,&{{ y}})
\end{array}
\\\\\\
% slope = m
slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ y_2}}-{{ y_1}}}{{{ x_2}}-{{ x_1}}}\implies \cfrac{y-2}{5-2}=\stackrel{slope}{2}\implies \cfrac{y-2}{3}=2
\\\\\\
y-2=6\implies y=8[/tex]
