The distance between the points $(2,3)$ and $(2,8)$ is

1. The x-coordinates are equal, so the segment is vertical. 2. Distance $=\sqrt{(2-2)^2+(8-3)^2}=\sqrt{0+25}$. 3. $=\sqrt{25}=5$ units. _Source: Karnataka SSLC (KSEEB) Class 10 Mathematics, Ch7 'Coordinate Geometry', §7.2_