Question

{x+y=13 {x-y=5 помогите

Answer 1

$left { {{x+y=13} atop {x-y=5}} right. ; oplus ; ominus ; left { {{2x=18} atop {2y=8}} right. ; left { {{x=9} atop {y=4}} right. \\Otvet:; ; (9,4); .$