7x-(3+2x)=x+9 Второе 13-(2x-5)=x-3

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7х-(3+2х)=х+9                     13-(2х-5)=х-37х-3-2х=х+9                         13-2х+5=х-35х-3=х+9                              18-2х=х-35х-х=3+9                              -2х-х=-18-34х=12                                   -3х=-21х=12/4                                   х=-21/-3х=3                                         х=7                    ответ:3                                 ответ:7