We can't find the perimeter if we don't know the length of the sides. Anyway, just add the lengths of all sides, that's how you find perimeter.
Find The Perimeter Of Each Triangle To The Nearest Centimeter. This Is Third Grade Math What Is The Perimeter? What Is An Centimeter?
A centimeter is a unit used for measuring distance. It is one hundredth of a meter. A meter is very roughly 10% longer than a yard. A centimeter is very roughly 4/10 of an inch. Metric units and their conversions can be found here.