\[y = - 3x\]
\[x = 1:\]
\[y = - 3 \cdot 1 = - 3.\]
\[x = 2:\]
\[- 3 \cdot 2 = - 6.\]
\[x = - \frac{3}{2}:\]
\[y = - 3 \cdot \left( - \frac{3}{2} \right) = \frac{9}{2} = 4,5.\]
\[x = - 1:\]
\[y = - 3 \cdot ( - 1) = 3.\]