87-х=39
-х=39-87
-х=-48
х=48
х+24=43
х=43-24
х=19
(38+y)-18=31
38 + y – 18 = 31
y = 31 + 18 – 38
y = 11
604+(356-y)=887
604 + 356 – y = 887
– y = 887 – 356 – 604
-y = -73
y = 73
87-х=39
-х=39-87
-х=-48
х=48
х+24=43
х=43-24
х=19
(38+y)-18=31
38 + y – 18 = 31
y = 31 + 18 – 38
y = 11
604+(356-y)=887
604 + 356 – y = 887
– y = 887 – 356 – 604
-y = -73
y = 73