In  the right   triangle    shown,  one leg is  30, and the hypotenuse  is  50. This    is
10  times   3-4-5.  The other   leg is  40.
86 .    The 5-12-13 Triangle
If  a   right   triangle’s  leg-to-leg  ratio   is  5:12,   or  if  the leg-to-hypotenuse   ratio   is
5:13    or  12:13,  then    it’s    a   5-12-13 triangle,   and you don’t   need    to  use the
Pythagorean theorem to  find    the third   side.   Just    figure  out what    multiple    of
5-12-13 it  is.
Here    one leg is  36, and the hypotenuse  is  39. This    is  3   times   5-12-13.    The
other   leg is  15.
87 . The 30-60-90 Triangle
The sides   of  a   30-60-90    triangle    are in  a   ratio   of      You don’t
need    the Pythagorean theorem.
