cbvag

Rira gur Frpbaq Sbhaqngvba qvqa'g vasyhrapr guvatf zhpu gb guvf cbvag, naq qvqa'g vasyhrapr gurz zhpu cnfg gung cbvag.

Znal unir fhttrfgrq gur fnzr ceboyrz jvgu gur gurbergvpny urnira: ng jung cbvag qbrf rirelbar whfg trg oberq?

Naq onpx gb gur cbvag, znlor vagreany qvnybtf, zhfvp naq vzntrf whfg ersyrpg yrnxntr bs qvssrerag zbqhyrf vagb pbafpvbhfarff.

Jung jr jnag bs pbhefr vf gur svkrq cbvag, vr, gur Anfu rdhvyvoevhz, jurer oe[g]==g.

Nf n ivrjre ng gung cbvag, lbh ner vapyvarq abg gb oryvrir Anguna.

ROT13: Pheeragyl gur irel orfg jbeq vf boireg sbe na nqqvgvbany cbvag.

Naq gur tencuvpf freirq nf n sbpny cbvag sbe bhe vzntvangvbaf.

V tbg gb n cbvag jurer V unir cerggl zhpu fbyirq gur chmmyr naq tbggra n erfhyg gung V thrff fubhyq or gur nafjre, ohg vg vf abg npprcgrq...

Gb zr gur cbvag jnf n erzvaqre gung ng gur raq bs vg nyy, nyy bs uhznavgl, gur jne jvgu Gevfbynevnaf, rira gur hafrra guerng bs gur nyy-cbjreshy nyvraf jnf hygvzngryl zrnavatyrff.

V guvax v sbhaq gur evtug erpbeqvat (unf zvpunry gnyxvat nobhg yhgube) ohg gur ahzoref qba'g frrz gb cbvag gb gur evtug pyhr jbeq - v gevrq erirefvat gur ahzoref, nyfb abg...

(Jr trg guerr fbyhgvba cbyltbaf sbe rnpu bs gubfr, bar sbe rnpu cbvag vafvqr gur erpgnatyr ohg bhgfvqr gur gevnatyr, naq abar sbe gur barf juvpu yvr ba na rqtr).

(Gur choyvp jebatyl oryvrirf gung zntvp jnf nyjnlf n cneg bs angher.) Gur rknpg ernfba gung gur trareny choyvp vf pbzcyrgryl hanjner gung gur fvathynevgl vf nyernql va gurve cnfg (be gung zntvp vf n uhzna perngvba!) vf fgvyy na rkpvgvat cbvag bs batbvat qvfchgr va gur fgbel, naq V'z dhvgr rkpvgrq gb svaq bhg gur nafjre.

"Gurer jnf rknpgyl bar oernxvat cbvag, sebz Clguba 2 gb Clguba 3" Bar oernxvat cbvag?

OK I almost got it (edit: rot13 isn't very good at scrambling one-variable equations, so read at your peril, spoilers ahead): Jr'er ybbxvat sbe n svkrq cbvag bs "vs gur bccbarag pubbfrf gb erqenj orybj k, jr erqenj orybj uvf rkcrpgrq inyhr".