Answer
Quadratic Formula
Work Step by Step
Using $ax^2+bx+c=0,$ the given equation, $
x^2+5x-8=0
,$ has
\begin{align*}
a=
1
,\text{ }b=
5
,\text{ and }c=
-8
.\end{align*}
Using the discriminant of a quadratic equation, which is given by $b^2-4ac,$ then
\begin{align*}
b^2-4ac&=
(5)^2-4(1)(-8)
\\&=
25+32
\\&=
57
.\end{align*}
Since the discriminant is NOT a perfect square, then the given equation is NOT factorable. Hence, the most appropriate way to solve the given equation is to use the Quadratic Formula.