Open a pair of compasses so the distance is slightly longer than the distance from P to the line. Place the compass at point P and draw two arcs, crossing the line either side of P Image caption ...

A protractor is used to draw and measure angles. An angle is the amount of turn between two lines. Angles are measured in degrees with the symbol °. Angles can be labelled with 3 letters (eg DEF ...

This marks the beginning of an extraordinary e-mail exchange, which can only be held between two strangers. Treading the fine line between complete strangeness and noncommittal intimacy ...