[tex]a)8 {x}^{2} + 3x - \frac{1}{2} = \frac{1}{2} (16 {x}^{2} + 6x - 1) = \frac{1}{2} (16 {x}^{2} + 8x - 2x - 1) = \frac{1}{2} (8x(2x + 1) - (2x + 1)) = \frac{1}{2} (2x + 1)(8x - 1)[/tex]
[tex]b) - \frac{1}{10} {x}^{2} - x - 20 = \frac{1}{10} ( - {x}^{2} - 10x - 200) [/tex]
