equilateral triangle

edinadilagic shared this problem 1 month ago
Not a Problem

Hello


There is a bug in the code. All three angles of an equilateral triangle are always 60°. Check the image.

Comments (5)

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this is not a bug but an example of rounding. Of course one cannot check this on a printscreen but on a file itself. In the picture the rounding is on 1 decimal so that all edges look the same. If you set the rounding on more decimals, I'm sure you'll notice the triangle isn't equilateral.

You get this kind of things if you create a triangle with three free points and you want to drag them into an equilateral triangle by dragging the points. If not on grid points, it's very hard to drag them perfectly to avoid things like you show in your post.

chris

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I thought it would round off automatically

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The rounding od the edges on 1 decimal doesn't correspont exactly at the same time with the rounding of the angles because there two different types of numbers. That's why edges can seem equal (by rounding) why angles just differ enough from each other to show there's not (just as the edges in fact aren't).

You get the same feature with edges and areas. Where edges seem to be equal (with 1 decimal) the shown areas can look different because of the square. E.g.: a square with edges of 5.52 has an area of 30.47 (shown as 30.5) whereas a square with edges of 5.51 has an area of 30.36 (30.4). In an applet the edges look equal on 1 decimal, the areas not.

That's the same with any calculator. If you calculate and check with just the shown values, you seem to be confronted with errors everywhere.

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I know about rounding and also that there are two diffrent numbers.

I didn't think about it when I was drawing.

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2

the triangle is not equilateral

please, round numbers to 5 decimals

the sides are not equal

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