I have no idea what Odalv is talking about, he makes these claims about simultaneous equations but he seems not to understand the math at all. He previously claimed you could steal coins that way, but I guess he's given up on that nonsense now and moved on to some other likely nonsense.
Yes, you are right. I was wrong with my claim I can compute Monero private key. -> I'm not so good :-) ... nevermind.