а) => (х-3)∙3 = 7∙ 6=> 3х-9 =42 => 3х = 51 => х = 17;
б) =>5 ∙ 45 = (2х + 3) • 2,5 => 22,5 = 5х + 7,5=> 5х = 15=> х = 3;
в) => (х + 7) • 5 = (2х - 3) • 3=> 5х + 35 = 6х-9=>х = 44;
г) =>0,2∙(х-2) = 0,7∙(х + 3) => 2х - 4 = 7х + 21=> -5х = 25=>х= -5. (Надеюсь
а) => (х-3)∙3 = 7∙ 6=> 3х-9 =42 => 3х = 51 => х = 17;
б) =>5 ∙ 45 = (2х + 3) • 2,5 => 22,5 = 5х + 7,5=> 5х = 15=> х = 3;
в) => (х + 7) • 5 = (2х - 3) • 3=> 5х + 35 = 6х-9=>х = 44;
г) =>0,2∙(х-2) = 0,7∙(х + 3) => 2х - 4 = 7х + 21=> -5х = 25=>х= -5. (Надеюсь