# If $\sqrt {9x^2+6x+1} < (2-x) ,$ then :

$\begin {array} {1 1} (a)\;x \in \bigg(-\frac{3}{2},\frac{1}{4}\bigg) & \quad (b)\;x \in \bigg( -\frac{3}{2}, \frac{1}{4}\bigg] \\ (c)\;x \in \bigg[ -\frac{3}{2}, \frac{1}{4}\bigg ) & \quad (d)\;x < \frac{1}{4} \end {array}$

$(a)\;x \in \bigg(-\frac{3}{2},\frac{1}{4}\bigg)$