Answer
$\{-\frac{2}{7},5 \}$
Work Step by Step
Step 1. Let $u=(x)^{-1}$, we have $10u^2+33u-7=0$
Step 2. Factor and solve: $(5u-1)(2u+7)=0$ thus $u=-\frac{7}{2}, \frac{1}{5}$
Step 3. For $u=-\frac{7}{2}$, we have $(x)^{-1}=-\frac{7}{2}$ thus $x=-\frac{2}{7}$
Step 4. For $u=\frac{1}{5}$, we have $(x)^{-1}=\frac{1}{5}$ thus $x=5$
Step 5. Solution set $\{-\frac{2}{7},5 \}$
