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If I have a square with side $2\ \text{km}$, what is its area: $2\ \text{sq km}$ or $4\ \text{km}^2$?

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The area is $4$ sq. km. or $4\text{ km}^2$. The units square kilometer and $\text{ km}^2$ mean the same thing. – Brian M. Scott Sep 26 '12 at 10:17
How many 1kmx1km squares can you fit in it? Ergo? – Did Sep 26 '12 at 10:17
Or you can say: open parenthesis two kilometer closed parenthesis squared: $(2~\mathrm{km})^2$. :-) – Willie Wong Sep 26 '12 at 10:21
The notation $4\,\mathrm{km}^2$ will be understood all over the world. The notation $4\,\mathrm{sq. km}$ only in English speaking countries. – celtschk Sep 26 '12 at 10:28
up vote 3 down vote accepted

A square with side $2\ \text{km}$ has area $4\ \text{km}^2$. This is pronounced as four square kilometres.

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Suppose that a triangle has $\text{height = }a \text{ cm}, \text{ base = }b \text{ cm}$. The area, in mathematical notation, is $\Large {a\cdot b \over 2} \normalsize \text{cm}^2 $.

You may pronounce the above as the quantity a times b all over two square centimeters, even though there is no difference at all.

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Your area formula is a factor of 10,000,000,000 off. – Henning Makholm Sep 26 '12 at 13:32
@Henning: Thanks, I just got it right. – Parth Kohli Sep 26 '12 at 13:48
But now the pronunciation is wrong. – Henning Makholm Sep 26 '12 at 14:11
Heh, you're a lifesaver. – Parth Kohli Sep 26 '12 at 14:23
@Hennig. What do you mean by your comment 10-billion off – VAR121 Sep 27 '12 at 4:26

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