What is the first step in the construction of a line perpendicular to and passing through an external point m? assume that the construction uses only a compass and a straightedge.

With M as center we draw an arc which intersects given line at two points X & Y

Step-by-step explanation:

Given: let say a line AB and an external point M.

We have to write the first step to be used to construct a line perpendicular to line AB and passing through point M.

We can use only Compass and scale.

Perpendicular lines are the lines which intersects and form a right angle at point of intersection.

We suppose a line AB is already drawn and An external Point M.

After this the Next and important that we do is as following:

With M as center we draw an arc which intersects line AB at two points X & Y