The formula sheet furnished to students taking standardized tests in my state says that the area of a rectangle = length x width. But when I present this formula to students it's not obvious to me which is which.
If I'm looking at an index card, oriented either vertically or horizontally, I designate as "width" what my eye reads from left to right. But the second dimension doesn't seem to be "length"; it's height or tallness.
On the other hand, I have no trouble perceiving a swimming pool as 50 meters long and 25 meters wide.
I tend to focus on "x times y" vs. "l x h" to get across the idea multiplying the two dimensions. They know there's "more room" on both sides of an 3x5 index card than on one side of an 8.5 x 11 piece of paper, but then the term "area" can totally throw them, let alone "dimensions."
So I want feedback: What's best for clarity?
If I'm looking at an index card, oriented either vertically or horizontally, I designate as "width" what my eye reads from left to right. But the second dimension doesn't seem to be "length"; it's height or tallness.
On the other hand, I have no trouble perceiving a swimming pool as 50 meters long and 25 meters wide.
I tend to focus on "x times y" vs. "l x h" to get across the idea multiplying the two dimensions. They know there's "more room" on both sides of an 3x5 index card than on one side of an 8.5 x 11 piece of paper, but then the term "area" can totally throw them, let alone "dimensions."
So I want feedback: What's best for clarity?
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