Answer :

[tex]-7w+3(w+6)=30\\\\-7w+3w+18=30\\\\-4w+18=30\ \ \ \ \ |subrtact\ 18\ from\ both\ sides\\\\-4w=12\ \ \ \ \ \ |divide\ both\ sides\ by\ (-4)\\\\\boxed{w=-3}[/tex]
View image Аноним
[tex]-7w+3(w+6)=30\\ -7w+3w+18=30\\ -4w=12\\ w=-3[/tex]