Re:An update on the campaign to defend serious math educatio...
by snvzz on Tuesday April 26, 2022 @04:40PM
(#31172879)
>Then I drew a square and was done.
I don't get this part.
You mean to highlight the end result? In that case, it would, most of the time, be a rectangle (or try to be).
Re:An update on the campaign to defend serious math educatio...
by texaslonghorn5 on Tuesday April 26, 2022 @04:52PM
(#31173028)
I was joking, I meant the QED box.
Re:An update on the campaign to defend serious math educatio...
by snvzz on Tuesday April 26, 2022 @05:06PM
(#31173179)
I know about QED, but I am not familiar with the concept of "QED box".
A cursory web search yielded nothing.
Re:An update on the campaign to defend serious math educatio...
by ludwigschubert on Tuesday April 26, 2022 @05:21PM
(#31173354)
It’s a symbol that goes by many names: the tombstone, end-of-proof, or Q.E.D.
"∎"
10x+7 = -2x+31
Move 7 to the other side (picking up a minus sign)
10x = -2x + 31 - 7 = -2x + 24
Move -2x to the other side (flipping sign)
12x = 24
Recover 12*2 = 24 via memorization, quick division (though not long division), or whatever method
Therefore, x = 2. Then I drew a square and was done.