Perimeter and area

Question

How to find the perimeter if we only have the width of 18 and we don’t have area

Answer 1

We do not know the shape that you are dealing with. However, it turns out that some shapes you can find both perimeter and surface area using only the width. One example, as Jacques D. pointed out, is a square: since all sides are equal, you can simply add each side to find perimeter (18+18+18+18) and you are finished. Another example is a circle: with a width (or diameter, in this case) of 18, you can find the perimeter (or circumference) by multiplying the width by pi. Finally, you may have a certain kind of triangle (equilateral, right, etc.) that allows you to find perimeter just from width. For example, in the case of a right triangle with two equal sides, you can use the pythagorean theorem. If none of these work, perhaps you have additional information about the shape that you missed---be sure to look carefully at the problem to figure out exactly what information you have.

Answer 2

It is impossible unless you know it's a square, or are given some other piece of information.

Answer 3

You can't unless you are told it is a square.