Answer:
Their sides must be in the same ratio and their angles must be equal.
Step-by-step explanation:
If two polygons are similar their sides must be in the same ratio and their angles must be equal.
e. g. -
If ABCDEF and GHIJKL be the two polygons,
then,
and,
∠ABC = ∠GHI ; ∠BCD =∠HIJ ; ∠CDE = ∠IJK ; ∠DEF =∠JKL ; ∠EFA =∠KLG;
∠FAB = ∠LGH .