If it’s a square 381km x 381km then that’s 145161km² (and I’m not aware that there’s any difference between “square kilometres” and “kilometres squared”, is there?)
It’s very common to use km^2 (or m^2 or whatever) as a unit of area, with the understanding that a square with x km sides has area x^2 km^2.
I can see what you’re saying, but I think most people would call that area ‘over 145 000 square km’ or something, rather than talk about the side length.
In writing it’s not clear, but in spoken word you usually stress it like (381 kilometers) *pause* squared, which makes it clear the square applies to both value and unit, (381km)², whereas 381 (kilometers squared) is just 381km²
If it’s a square 381km x 381km then that’s 145161km² (and I’m not aware that there’s any difference between “square kilometres” and “kilometres squared”, is there?)
Square x and x squared is the same thing. The proper way to say this is “A square of 381 km width”
It’s very common to use km^2 (or m^2 or whatever) as a unit of area, with the understanding that a square with x km sides has area x^2 km^2. I can see what you’re saying, but I think most people would call that area ‘over 145 000 square km’ or something, rather than talk about the side length.
In writing it’s not clear, but in spoken word you usually stress it like (381 kilometers) *pause* squared, which makes it clear the square applies to both value and unit, (381km)², whereas 381 (kilometers squared) is just 381km²