Answer
$d = 7.81$
Work Step by Step
$P_1 = (-1,2,3)$
$P_2 = (2,-2,9)$
We can find the distance between these two points:
$d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2}$
$d = \sqrt{(2-(-1))^2+((-2)-2)^2+(9-3)^2}$
$d = \sqrt{(3)^2+(-4)^2+(6)^2}$
$d = \sqrt{9+16+36}$
$d = \sqrt{61}$
$d = 7.81$