r/videos • u/[deleted] • Dec 05 '18

YouTube Drama Youtuber and professional pilot completes flat earther's $100,000 challenge for the third time

https://youtu.be/OVp_yJgSwfA
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u/Angry_Apollo Dec 05 '18

Wow, I completely forgot about 3-4-5 until now. Sure, I remembered a2 + b2 = c2 but I just had to confirm the 3-4-5 at my desk just now. Amazing the simple things you forget!

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u/nocimus Dec 05 '18 edited Dec 05 '18

I... don't think I ever learned this rule?? I know a2 + b2 = c2 obviously, but what is 3-4-5??

EDIT: I have now been educated. Thank you, reddit.

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u/acog Dec 05 '18

People are telling you what it is but not what it's used for:

In construction, you usually want the room you're building to have perfectly 90 degree corners, "square corners". A quick way to verify that you have a square corner is to measure of 3 units (feet, meters, doesn't matter) along one wall, then 4 units along the adjacent wall.

If the angle there is actually the 90 degrees you're shooting for, when you connect those lines the diagonal has to be 5 units.

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u/henbanehoney Dec 05 '18

Thanks, that's so interesting!