1)х-50,6+2,15=42,9
х=42,9+50,6-2,15
х=91,35
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(91,35-50,6)+2,15=42,9
40,75+2,15=42,9
42,9=42,9
2)31,28-m-4,2=15,093
-m=15,093-31,28+4,2
-m= -16,187+4,2
-m= -11,987
m=11,987
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31,28-(11,987+4,2)=15,093
31,28-16,187=15,093
15,093=15,093