Answer
$x=-0.53$ or $x=-3.37$
Work Step by Step
We are given:
$x^{2}+3.9x+1.8=0$
We solve using the quadratic formula ($a=1,\ b=3.9,\ c=1.8$):
$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$
$x=\displaystyle \frac{-3.9\pm\sqrt{(3.9)^{2}-4*1*1.8}}{2*1}$
$x=\displaystyle \frac{-3.9\pm\sqrt{15.21-7.2}}{2}$
$x=\displaystyle \frac{-3.9\pm\sqrt{8.01}}{2}$
$x=-0.53$ or $x=-3.37$
