\(\left(2-1\right)f\left(2\right)+3f\left(-2\right)=5-2\Leftrightarrow f\left(2\right)+3f\left(-2\right)=3\)
\(\left(-2-1\right)f\left(-2\right)+3f\left(2\right)=5+2\Leftrightarrow-3f\left(-2\right)+3f\left(2\right)=7\)
\(\Leftrightarrow-3f\left(-2\right)+3\left(3-3f\left(-2\right)\right)=7\Leftrightarrow-12f\left(-2\right)=-2\Leftrightarrow f\left(-2\right)=\frac{1}{6}\)