Answer
$1.118, \ or, \ -1.118$
Work Step by Step
For the equation $4x^2 -5= 0$, we use the quadratic formula as follows
$$
x=\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a},
\\
a=4, \quad b=0, \quad c=-5
.$$
That is, $$ x=\frac{0\pm \sqrt{0+80}}{2(4) }=1.118, \ or, \ -1.118
.$$
