1:=>x-1=0 và y=0
=>x=1 và y=0
2: =>\(\left(x,y\right)\in\left\{\left(1;15\right);\left(3;5\right);\left(5;3\right);\left(15;1\right)\right\}\)
3: \(\Leftrightarrow\left(2x-1;y+2\right)\in\left\{\left(1;24\right);\left(3;8\right)\right\}\)
hay \(\left(x,y\right)\in\left\{\left(1;22\right);\left(2;6\right)\right\}\)