Answer
$x=\left\{
-4,2.5
\right\}$
Work Step by Step
The standard form of the given equation is
\begin{align*}
2x^2+8x-5x-20&=0\\
2x^2+3x-20&=0
\end{align*}
Using a graphing software, the graph of the given equation is shown below.
The solutions of the equation are the $x$-values when the graph crosses the $x-$axis. Hence, based on the graph, the solutions are $
x=\left\{
-4,2.5
\right\}
.$
