#### Answer

$x=9$, $x=4$

#### Work Step by Step

$x-5\sqrt{x}+6=0$
We make the substitution $y=\sqrt{x}$. The equation becomes:
$y^{2}-5y+6=0$
$(y-3)(y-2)=0$
$y-3=0$ or $y-2=0$
$y=3$ or $y=2$
We find the $x$ solutions with the $y$ solutions:
$y=\sqrt{x}$
$x=y^2$
For $y=3$:
$x=3^2=9$
For y=2:
$x=2^2=4$