To get the most from a direct box, your mixing board must have balanced mic and/or line inputs! (Note that some mixers offer both XLR and 1/4 balanced inputs -- check your manual.) Use a direct box if you are experiencing hum, buzz, or radio interference, or if your instrument's cable is longer than 20 feet.
When a transversal (any line that passes through two parallel lines) cuts two parallel lines then the angles that correspond to the similar positions (angles in the matching corners) with respect to either of the parallel lines and lie on the same side of the transversal are called the Corresponding angles.
Complementary or Supplementary Angles. Two angles are complementary if the sum of their angles equals 90o. If one angle is known, its complementary angle can be found by subtracting the measure of its angle from 90o.