[tex](2k,3) \\
x_1=2k \\ y_1=3 \\ \\
(1,k) \\ x_2=1 \\ y_2=k \\ \\
\hbox{the slope: } m=\frac{y_2-y_1}{x_2-x_1}=\frac{k-3}{1-2k}[/tex]
The slope is equal to 2.
[tex]\frac{k-3}{1-2k}=2 \\
k-3=2(1-2k) \\
k-3=2-4k \\
k+4k=2+3 \\
5k=5 \\
k=\frac{5}{5} \\
\boxed{k=1}[/tex]
