It depends on the shape. There are different formulae for different shapes.
rectangle
Add all sides together to get the perimeter.
if the angles of a figure are the same but the sides aren't, it is similiar. Congruent is angles and sides exactly the same
Congruent because the sides of an equilateral figure are of the same length.
Congruent because the sides of an equilateral figure are of the same length.
Any figure with 6 sides is a Hexagon. If all sides of the figure are of the same length, and all interior angles are 120° then you have a regular hexagon.
Geometry
An equilateral figure means that the figure has all sides that are the same length.
A trapezoid
a polygon
A square
measure it's sides and then multipy them.