(212z-199z)-9=30
13z=30+9
13z=39
z=39:13
z=3
(410y-395y)+9=84
15y=84-9
15y=75
y=75:15
y=5
1000-(501x+19x)=480
520x=1000-480
520x=520
x=520:520
x=1
999+(602z-582z)=2199
20z=2199-999
20z=1200
z=1200:20
z=60
13z=21
Z=21-13
Z=8
(212z-199z)-9=30
13z=30+9
13z=39
z=39:13
z=3
(410y-395y)+9=84
15y=84-9
15y=75
y=75:15
y=5
1000-(501x+19x)=480
520x=1000-480
520x=520
x=520:520
x=1
999+(602z-582z)=2199
20z=2199-999
20z=1200
z=1200:20
z=60