Parallel lines are straight lines which have the same direction and so never meet ... lines meet an intersecting transversal, pairs of angles with particular properties are made.

The angle measures 135°. Always check which two numbers the angle is in between and remember the direction the numbers are going in. It is easy to make a mistake and write 145° instead.

Introduction Change of direction (COD) manoeuvres are important for many field sports, however they are unfortunately associated with non-contact ACL injuries. Although players frequently COD at >90° ...

Then, once the angle is reached, the complete drillstring is rotated, including the bend, ensuring the drillbit does not drill in a different direction from the wellbore axis. One type of ...