Answer
$x=2$
Work Step by Step
Step 1. Rewrite the equation as $3-\sqrt {x-1}=\sqrt {x+2}$
Step 2. Take square on both sides to get $9-6\sqrt {x-1}+x-1=x+2\longrightarrow 6\sqrt {x-1}=6$
Step 3. We can get the solutions $x-1=1^2$ and $x=2$
Step 4. Check the answer with the original equation, we find it fits.