Alright, start with simplifying both sides
[tex] \frac{2}{7} k+ \frac{-3}{8} = \frac{-19}{8} [/tex]
Than add [tex] \frac{3}{8} [/tex] to both sides.
[tex] \frac{2}{7}k + \frac{-3}{8} + \frac{3}{8} =\frac{-19}{8} + \frac{3}{8}[/tex]
which is [tex] \frac{2}{7} k=-2[/tex]
After this, multiply each side by [tex] \frac{7}{2} [/tex]
[tex]( \frac{7}{2})* \frac{2}{7} k= ( \frac{7}{2})*(-2)[/tex]
So, your final answer is K=-7
