• Urist@lemmy.blahaj.zone
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    11 months ago

    x cant be both values at the same time, not under what most people consider to be math. Feel free to write your own logical system and see where that takes you, though.

    I think the only “solution” that works is addition/subtraction under mod 4 (or mod 2 I suppose) like another poster suggested. Then we’d have:

    X + 2 = x - 2

    X + 4 = x (Add 2 to both sides)

    X + 0 = x (4 = 0 mod 4)

    X = x (True for all x)

    • 0x4E4F@sh.itjust.worksOP
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      11 months ago

      (True for all x)

      But not true for any rational number if you try it in the equation.

      Thus, this is not a solution. The equation is unsolvable with rational numbers.

      • Urist@lemmy.blahaj.zone
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        11 months ago

        Correct, not solvable with rational numbers. I should have been more clear. When we’re doing arithmetic modulo x, it’s assumed to be with integers.

        To be clear, this is a solution only in Z_4 which is not what most people mean when they’re look for answers to algebra problems. And it would be a solution for all x in Z_4 (which are integers, see this page that I assume is a good summary)

        edit: this page might be better

        • 0x4E4F@sh.itjust.worksOP
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          11 months ago

          Yes, that is correct, this is solvable in modular algebra… but, in that case, the tripple horizontal line equal sign should have been used, not the double horizontal line one, which of course indicates classic algebra.

          • Urist@lemmy.blahaj.zone
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            11 months ago

            Also true but I’m not sure how to do that on my phone so I gave up

            Maybe lemmy can do mathjax someday

            • 0x4E4F@sh.itjust.worksOP
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              11 months ago

              I was talking about the person that posted the equation. They should have found a way if they wanted this thing solved, lol 😂.