Юльчикlike 4.2x+30.24=30.996
4.2x=30.996-30.24
4.2x=0.756
x=0.756:4.2
x=0.18

Phonis (x+7,2)*4,2=30,996
4,2x+30,24 = 30,996
4,2x = 30,996-30,24
4,2x=0,756
x=0,756/4,2
x=0,18