Question

Укажите решение системы нерввенст x>9
4-x<0

Answer 1

$\left \{ {{x>9} \atop {4-x<0}} \right. <=>\left \{ {{x>9} \atop {-x<-4}} \right. <=>\left \{ {{x>9} \atop {x>4}} \right.$

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                                   $x>9$    - общее решение

Ответ:  $(9; +\infty)$