# “10-cm square” is OK?

I'd like to say that we need to draw a square of which each edge length is 10 cm (i.e., 100 square cm).

What is the simplest way to represent such shape? Is the following sentence makes sense?

We need to draw a 10-cm rectangle.

We need to draw a rectangle each side 10 cm.

I think this is a very boring and childish question. However, this kind of simple thing is sometimes difficult for non-native English speakers. Please help.

• I would use a 10-(cm-)by-10-cm square. I'm not sure if a 10-cm square really works. Maybe, maybe not. – Damkerng T. Mar 30 '16 at 1:16

First of all, all squares are rectangles, but we probably wouldn't call it a "rectangle" if it were actually a square.

We need to draw a rectangle...

we would say:

We need to draw a square...

Now there's the part about how to best describe the square – which is anything but childish! There are a few ways to do this:

We need to draw a square with 10 cm sides.
We need to draw a square where each side is ten centimeters long.

If we want more brevity, though, we can also use 10 cm as an adjectival phrase modifying the word square:

We need to draw a 10 cm square.

That's the technique used on this web page:

Cut a 10 cm square piece of wax paper and a 10cm square piece of plastic wrap.

• Wow, thank you! Both longer and brevity expressions are helpful for my purpose. How great community here is... – Light Yagmi Mar 30 '16 at 1:52

J.R.'s answer is excellent. There is one very brief way to refer to a square he didn't mention:

# "by" # can be used if the units are obvious or unimportant. For instance:

The teacher gave each of his students a ruler and told them to draw a four by four square on a piece of writing paper.

Here we may not know if the square is meant to be 4"x4" or 4cm x 4cm. Most Americans would assume the former, the rest of the world would assume the latter.

Context could inform that, though.

First the teacher had his student draw a circle with a 3 inch radius. Then he asked them to draw a two by two square inside the circle, and a seven by ten rectangle around the circle.

• You could use this and also include the units: "Draw a 10 cm by 10 cm square." But in that case the "# by #" is an adjective, so you should end with "square" or "rectangle". – joeytwiddle Apr 1 '16 at 10:25
• Of related interest, it's also the norm in construction and other trades to say of a 10-ft by 10-foot space, "this room is ten feet square"; or of a 100'x100' plot of land, "this plot is 100 feet square". Accordingly, it's rare and confusing to say "feet squared" in place of "square feet", even if it's being written as ft². – CCTO Sep 14 '20 at 17:23