#ALgebra

62 messages · Page 1 of 1 (latest)

fiery nest
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HELPPPPPP i wanna solve this but without squaring both sides (using a clever trick)
ig imon the right ath but dont seem to find the right answer, enter the thread to see my though process

azure nymphBOT
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fiery nest
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using the last equation on wolfram im not getting the correct answer

tawdry remnant
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i mean 69 + 6 =/= 71

fiery nest
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bruh

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my bad

tawdry remnant
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doing it by squaring both sides is also not that bad

fiery nest
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hefty long solution

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and i got it with my way tooo

tawdry remnant
fiery nest
tawdry remnant
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yeah you get the same quadratic, -x^2 + 138x - 4761, the other way

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so, conveniently, 138^2 = 4*4761

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so the discriminant is 0

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however good luck working that out

fiery nest
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i dont like substituting y+x^2 type

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my purpose was an aproach different than normal one

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after all im giving the second toughest exam

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anyways thank you

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: D

tawdry remnant
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was this a real question from a test

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the 69 answer makes me think not

fiery nest
tawdry remnant
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i wonder if there is some very slick number theory way if you assume the answer is an integer

fiery nest
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number theory scares me 💀

tawdry remnant
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we need a^2 | x + 36, b^2 | (2x-33)
actually
x + 36 = na^2, 2x-33 = nb^2, 6x+6 = n(a+b)^2
n,b both odd, so a is also odd, so x is odd

fiery nest
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lemme make this out

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if x+36 = na^2
wouldnt 2x-33 = mb^2?

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howd we know its the same factor for both (n)

tawdry remnant
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the power of intuition

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nah im not sure but i think if that is true it should be figureoutablewhy

fiery nest
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we cant just assume it like that?

tawdry remnant
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we cant just assume x is an integer either

fiery nest
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did we?

fiery nest
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my bad

fiery nest
tawdry remnant
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| is only defined for integers, as is evenness/oddness

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some stuff may still be workable if you only assume x is rational

fiery nest
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ouh we studied this as if x|y x is divisible by y (x/y = integer)

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doesnt matter if x and y are integers or not

tawdry remnant
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thats a possibility

fiery nest
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yeah its what im talking about

sick shore
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andy math ?

fiery nest
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i aint watching his solution 💀

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i was just working out for some unique trick workeable on any question im stuck on

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just boosting my solving capabilities

tawdry remnant
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n,x are both 1 mod 4
3x = -1 mod 16 (from last equation, n == 1 mod 4, (a+b)^2 == 4 mod 4)
x = 5 mod 16
na^2 = nb^2 = 9 mod 16
so a = b or a = -b mod 16

fiery nest
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we havent studied mod and its propertiess 😭

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ill try to udnerstand ik to some extent

sick shore
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is mod the same thing as it is in programming

fiery nest
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remainder thing

sick shore
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yea thats it

echo plinth
tawdry remnant
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however if 16 | (a+b) then the lhs is a multiple of 256
meanwhile, 6x + 6 = 6(4k + 2) = 12(2x + 1)
which is not a multiple of 256
so a == b mod 16

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anyway, at this point i think this is harder than the normal method(s), but you can try doing it this way kind of like a puzzle

fiery nest
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im puzzled myself

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lemme work it out

fiery nest
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+close