Perimeter is like adding all the sides on a shape together, for example; one side has 12 inches while the other side is 15 inches, you would solve (12 x 2) + (15 x 2) which is 54in² and i know that because im smart hehe the answer will show up in a variable if you don't type in a number it will not work, the answer will show up as zero or as something else
this was kinda fun to make!