Bisecting an 180° angle is possible

kasperpeulen / euclidthegame

A geometry game based on Euclid's Elements.

euclidthegame.org

MIT License

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Bisecting an 180° angle is possible #243

Open Vampire opened 10 years ago

Vampire commented 10 years ago

The angle bisection tool lets you bisect a 180° angle by selecting three points on a line. At least with the method to get the tool this is not possible. This way you can solve Level 4 easily but wrongly.

kasperpeulen commented 10 years ago

@Vampire I think this is fixed in the development website: http://euclidthegame.me/Level4/

kasperpeulen commented 10 years ago

@Vampire Actually, now I think more about it, with method you get this tool, 180 degree angle seems perfectly valid, no ? Even more than 180 degrees seems to work with the method here http://euclidthegame.me/Level3/

Vampire commented 10 years ago

Yep, also played through the dev site now and there it is not possible. More than 180° is fine, but exactly 180° does not work. At least not with the method I used to solve Level 3. It was:

Draw an arbitrary circle around center A
Construct the midpoint between the intersection points
Draw ray from A through midpoint

For 180° the second step would bring out A itself as midpoint and so you have only one point to draw the ray which is not possible.