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
2 months ago

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nice idea. in line 4 you use the fact that -2 -x = -x -2 (Commutative Property).
you can avoid that by changing line 4 to:
-x +x -2 = -x
(this means -x is applied to the left of each of the sides. it avoids the use of the Commutative Property)

num IC - 2 days, 20 hours ago

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Ya everything about the note is useful, except for the fact that its not. This is basic knowledge. Only people who don't know a thing about the equal to symbol will need this!

Percy Jackson - 2 days, 19 hours ago

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i dont agree

num IC - 2 days, 19 hours ago

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Oh no hamza, oh god. I DIDN'T EVEN KNOW THIS STUFF!!! HATE MA TEACHERS

I Love Brilliant - 4 weeks 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

NSCS 747 - 1 month, 2 weeks ago

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

Percy Jackson - 1 month, 2 weeks ago

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none taken son

NSCS 747 - 1 month, 2 weeks ago

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@Nscs 747 haha very funny, I doubled over............................................................................................(note the sarcasm)

Percy Jackson - 1 month, 1 week ago

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

NSCS 747 - 1 month, 1 week ago

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@Nscs 747 .......................that isn't even worth replying to.

Percy Jackson - 1 month, 1 week ago

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

NSCS 747 - 1 month, 1 week 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 - 2 months 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 - 2 months 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 - 1 month, 4 weeks 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 - 1 month, 4 weeks ago

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