Question

помогите решить систему

Answer 1

$\left \{ {3y\ \textless \ 21 \atop {4-y\ \textgreater \ 0}} \right. \left \{ {{y\ \textless \ 7 \atop {-y\ \textgreater \ -4}} \left \{ {{y\ \textless \ 7\atop {y\ \textless \ 4} \right.$

ОТВЕТ: y ∈ (-∞;4)