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

$\large\begin{aligned} x &= 2 \\ x - 2 &= 2 - 2 \\ x - 2 &= 0 \\ x - x - 2 &= - x \\ - 2 &= - x \\ -2 × -1 &= -x × -1 \\ 2 &= x \end{aligned}$

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

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

#Algebra

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

@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 - 9 months, 3 weeks ago

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

And yes, mathematically, they are the same equation

Frisk Dreemurr - 9 months, 2 weeks ago

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 :)

A Former Brilliant Member - 9 months, 2 weeks ago

@A Former Brilliant Member – 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 - 9 months, 2 weeks ago

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 - 9 months ago

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

A Former Brilliant Member - 9 months ago

none taken son

NSCS 747 - 9 months ago

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

A Former Brilliant Member - 9 months ago

@A Former Brilliant Member – ok percy percy jackson jackson (implying the double)

NSCS 747 - 9 months ago

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

A Former Brilliant Member - 9 months ago

@A Former Brilliant Member – .......................that isn't even worth replying to.

NSCS 747 - 9 months ago

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 - 7 months, 3 weeks ago

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!

A Former Brilliant Member - 7 months, 3 weeks ago

i dont agree

num IC - 7 months, 3 weeks ago

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

I Love Brilliant - 8 months, 2 weeks ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

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

Comments