Answer
$\left\{4, 9\right\}$
Work Step by Step
Factor the trinomial to obtain:
$(x-9)(x-4)=0$
Equate each factor to zero then solve each equation to obtain:
$x-9 = 0 \text{ o } x-4=0
\\x=9 \text{ or } x=4$
The solution set of the given equation is $\left\{4, 9\right\}$.
