Question

Construct a line that is perpedicular to line m and that passes through point P.

Answer 1

Take the compass, and place the pointy end on the point m.. Then adjust the size until the pencil point of the compass is on point p, and make a circle.
Then, keep the compass on the same setting and put the pointy end on the other end of the line, and adjust it until the pencil tip is on point p again. Then draw another circle.
Now, connect the two places that the circles intersect in, using a ruler.