Помогите решить уравнения:1) 2( 6x+8 ) - 3x = 3132) 630:

1) 12х+16-3х = 313    3) ((42+33а)-27):60 = 30-27       4) (45-(7х-25))*4 = 58+26

      9х = 313-16              ((42+33а)-27):60 = 3                 (45-(7х-25))*4 = 84

      9х = 297                    (42+33а)-27 = 3*60                    45-(7х-25) = 84:4

       х = 33                        (42+33а)-27 = 180                     45-(7х-25) = 21

                                            42+33а = 180+27                    7х-25 = 45-21

                                            42+33а = 207                          7х-25 = 24

                                               33а = 207-42                        7х = 24+25

                                            33а = 165                                7х = 49

                                             а = 5                                        х = 7

2) 630:21х+53 = 68

    30х+53 = 68

     30х = 68-53

     30х = 15

       х = 15/30 = 1/2