## Algebra 2 (1st Edition)

$x=\displaystyle \pm i\frac{\sqrt{14}}{7}$
$7x^{2}-4=-6\qquad$ ...add $4$ to each side of the expression. $7x^{2}=-2\qquad$ ...divide each term with $7$. $x^{2}=-\displaystyle \frac{2}{7}\qquad$ ...take square roots of each side. $x=\pm\sqrt{-\frac{2}{7}}\qquad$ ...write in terms of $i$. $x=\displaystyle \pm i\frac{\sqrt{2}}{\sqrt{7}}\qquad$ ...rationalize the radical by multiplying both the numerator and denominator with $\sqrt{7}$. $\displaystyle \frac{\sqrt{2}}{\sqrt{7}}=\frac{\sqrt{2}\cdot\sqrt{7}}{\sqrt{7}\cdot\sqrt{7}}=\frac{\sqrt{14}}{7}$ $x=\displaystyle \pm i\frac{\sqrt{14}}{7}$