How to prove that x=2\boxed{x = 2} is the same as 2=x\boxed{2 = x}

x=2x2=22x2=0xx2=x2=x2×1=x×12=x\large\begin{aligned} x &= 2 \\ x - 2 &= 2 - 2 \\ x - 2 &= 0 \\ x - x - 2 &= - x \\ - 2 &= - x \\ -2 × -1 &= -x × -1 \\ 2 &= x \end{aligned}

Therefore, x=2 is the same as 2=x\text{Therefore, \boxed{x = 2} is the same as \boxed{2 = x}}

Just for clarification, this is meant to be a joke note, made due to a dare some friend of mine gave :)

Note by Frisk Dreemurr
3 weeks, 2 days ago

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@Frisk Dreemurr Your proof is just cancelling out or rearranging, throughout the whole proof, in a mathematical perspective, you have not changed the equation!

Shevy Doc - 3 weeks, 1 day ago

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Yes, that is why I thought to post it. It looks interesting, and not all know/tried to prove that 2=x2 = x is the same as x=2x = 2 before, they just take that fact for granted :)

And yes, mathematically, they are the same equation

Frisk Dreemurr - 3 weeks ago

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Its still useless. x = 2 says that their values are equal, so 2 = x doesn't convey more info and is useless. Also, there's an easier way to do what you did -

x = 2

-x = -2 (multiply by -1 on both sides)

2 = x (transposition, so -x becomes x on RHS and -2 becomes 2 on LHS)

This note isn't actually very interesting or effective. in all honesty. No offense @Frisk Dreemurr.

PS - Just finished the Atlantis Complex (7th book) and I'm dying, its awesome! BTW, today is Artemis Fowl's birthday, Sep 1st :)

Percy Jackson - 2 weeks, 4 days ago

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@Percy Jackson LOL, the challenge was to only use core traditional methods, so no transposition as well

Plus, I didn't mean this note to be much useful/interesting, as I made it for a joke :)

Frisk Dreemurr - 2 weeks, 4 days ago

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dont most of us know this it is simple algebra and most people cover this as a basic fundamental when they learn it in school its basically the same as learning operations in primary school and fractions and stuff its just that you add letters and mumbo jumbo language intoit to make a mixture of math that is good and useful if done right but sticky and messy if done wrong

Nathan Soliman - 4 days, 14 hours ago

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Exactly @Nathan Soliman, see @Frisk Dreemurr, even the 13 year old preschooler gets it, no offense 'Ethan' :)

Percy Jackson - 4 days, 11 hours ago

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none taken son

Nathan Soliman - 3 days, 15 hours ago

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@Nathan Soliman haha very funny, I doubled over............................................................................................(note the sarcasm)

Percy Jackson - 2 days, 22 hours ago

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@Percy Jackson ok percy percy jackson jackson (implying the double)

Nathan Soliman - 2 days, 18 hours ago

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@Nathan Soliman .......................that isn't even worth replying to.

Percy Jackson - 2 days, 17 hours ago

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@Percy Jackson .......................that isn't even worth replying to.

Nathan Soliman - 1 day, 16 hours ago

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