Answer
$-3, \ or, \ 0.2 $
Work Step by Step
For the equation $5x^2 +14x-3= 0$, we use the quadratic formula as follows
$$
x=\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a},
\\
a=5, \quad b=14, \quad c=-3
.$$
That is,
$$
x=\frac{-14\pm \sqrt{14^2+60}}{2(5) }=-3, \ or, \ 0.2
.$$
