512)
1) = -(2,6+1,4) -(0,3+9,7)= -4 - 10 = -14
2)= (1,5+8,5)-(5,4+1,6)=10-7=3
3)= (4,37+6,63)-(3,65+7,35)=11-11=0
4)= -(9,94+0,06) -(2,13-0,13)= -10-2=-12
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513
1)
-x=18,24-35,8
-x= -17,56
x=17,56
2)
-x=4,125-1,25
-x=2,875
x= -2,875
3)
-y= -13,56
y=13,56
4)
-y=14/21 - 9/21
-y=15/21=5/7
y= -5/7