Similar figures have equal corresponding angles and all corresponding distances in the same positive ratio,
called the ratio of magnification (Coxeter
and Greitzer 1967, p. 94). A transformation
that takes figures to similar figures is called a similarity.
Two similar figures are directly similar when all corresponding angles are equal and described in the
same rotational sense. This relationship is written .
(The symbol
is also used to mean "is the same order of magnitude as" and "is asymptotic to.") Two similar figures are inversely
similar when all corresponding angles are equal and
described in the opposite rotational sense.
.
(The symbol 
is also used to mean "is the same order of magnitude as" and "is asymptotic to.") Two similar figures are inversely
similar when all corresponding angles are equal and
described in the opposite rotational sense.
