The slope of the line is , [tex]-\frac{2}{3}[/tex]
Option B is correct.
Slope of line :
If a line passing through two points  [tex](x_{1},y_{1}),(x_{2},y_{2})[/tex]
Then , slope of line is,
           [tex]Slope(m)=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
The diagram below shown,
It is observed that, line passing through (3, 12) and (9, 8)
         [tex]Slope(m)=\frac{8-12}{9-3} \\\\m=-\frac{4}{6}=-\frac{2}{3}[/tex]
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