Question

Draw any line segment $\overline{AB}$. Mark any point M on it. Through M, draw a perpendicular to $\overline{AB}$. (Use ruler and compasses)

Answer 1

$\left(1\right)$ Draw the given line segment $\overline{AB}$ and mark any point M on it.
$\left(2\right)$ With M as centre and a convenient radius, construct radius, construct an arc intersecting the line segment $\overline{AB}$ at two points C and D.
$\left(3\right)$. With C and D as centres and a radius greater than CM, construct two arcs. Let these be intersecting each at E.
$\left(4\right)$ Join EM. $\overline{EM}$ is perpendicular to $\overline{AB}$.