(212z-199z)-9=30
212z-199z=30+9
11z=39
z=39/11
z=3,54545454545
1000-(501x+19x)=480
1000-501x-19x=480
1000-480=501x+19x
510=520x
520x=510
x=510/520
x=51/52
х=0,98076923076
(212z-199z)-9=30
212z-199z=30+9
11z=39
z=39/11
z=3,54545454545
1000-(501x+19x)=480
1000-501x-19x=480
1000-480=501x+19x
510=520x
520x=510
x=510/520
x=51/52
х=0,98076923076