Question

Решите уравнения

а)5x+(3x-7)=9; 

б)3y-(5-y)=11;

в)48=11-(9a+2); 

г)13-(5x+11)=6x; 

Answer 1

а) 5x + (3x - 7) = 9,

   5х + 3х - 7 = 9,

    8х - 7 = 9,

    8х = 9 + 7,

     8х = 16,

     х = 16 : 8,

     х = 2;

б) 3y - (5 - y) = 11,

    3у - 5 + у = 11,

     4у - 5 = 11,

      4у = 11 + 5,

      4у = 16,

       у = 16 : 4,

       у = 4;

в) 48 = 11 - (9a + 2),

    48 = 11 - 9а - 2,

     48 = 9 - 9а,

      9а = 9 - 48,

      9а = - 39,

      а = -39/9 = -13/3 = - 4 целые 1/3;

г) 13 - (5x + 11) = 6x,

    13 - 5х - 11 = 6х,

     2 - 5х = 6х,

      -5х - 6х = -2,

      -11х = -2,

       х = 2/11.