$\begin{array}{1 1} (a)\;\{\large\frac{1}{4},\normalsize 2\} \\ (b)\;\{\large\frac{-1}{3},\normalsize 2 \} \\ (c)\;\{\large\frac{1}{3},\normalsize -2\} \\(d)\;\{\large\frac{1}{3},\normalsize-2\} \end{array} $