Answer
$x=4$
Work Step by Step
$\sqrt {x-3}+1=\sqrt x$,
$\sqrt {x-3}=\sqrt {x} -1$,
Squaring both sides:
$x-3=x-2\sqrt x +1$,
$4-2\sqrt x=0$,
$4=2\sqrt x$
$2=\sqrt x$
Squaring both sides:
$x=4$
Check:
$\sqrt{4-3}+1=2$
$\sqrt 4=2$
$2=2\checkmark$