Question

А={(x,y)|2x-y=1}
B={(x,y)| x+y=5}
Переріз

Answer 1

$A=\{(x,y)\, |\, 2x-y=1\}\; \; ,\; \; \; B=\{(x,y)\, |\, x+y=5\}\\\\\\\left \{ {{2y-x=1} \atop {x+y=5}} \right.\; \oplus \; \left \{ {{3y=6} \atop {x+y=5}} \right.\; \; \left \{ {{y=2} \atop {x=5-y}} \right.\; \; \left \{ {{y=2} \atop {x=3}} \right. \; \; \Rightarrow \; \; \; A\cap B=(3,2)$