Answer
$x=1.038,x=-1.038$
Work Step by Step
Let $a=x^2$.
We get,
$3.2a^2-1.5a-2.1=0$
Using quadratic formula, $a=\frac{-(-1.5)\pm \sqrt{(-1.5)^2-4 (3.2)(-2.1)}}{2\cdot (3.2)}$
On solving, $a=-0.6089,1.0777$
Now, let's solve for $x$.
Since we need only real solutions of $x$, we only need to find $x$ for $a=1.0777$
$\implies x^2=1.0777$
$\implies x=\pm 1.038$
