\[y = - 4x\]
\[x = 4:\]
\[y = - 4 \cdot 4 = - 16;\]
\[x = 1:\]
\[y = - 4 \cdot 1 = - 4;\]
\[x = - 2,5:\]
\[y = - 4 \cdot ( - 2,5) = 10;\]
\[x = - 1:\]
\[y = - 4 \cdot ( - 1) = 4.\]