A)-3,8-5,7=-9,5 б)-8,4+3,7=-4,7 в)3,9-8,4=-4,5 г)-2,9+7,3=4,4
д)-2/9+5/6=(-4+15)/18=11/18 е)-1 3/4-2 1/2=-7/4-5/2=(-7-10)/4=-17/4=-4 1/4
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(-3,7-2,4)-(7/15-2/3)+5,9=0
1) -3,7-2,4=-6,1 2) 7/15-2/3=(7-10)/15=-3/15=-1/5 =-0,2 3) -6,1-(-0,2)=-5,9
4)-5,9+5,9=0
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x+3,12=5,43 1 3/14 - y=2 7/10
x=5,43-3,12 -y=27/10 -17/14
x=2,31 -y=(189 -84)/70
-y=105/70=-1 1/2
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3,7-(-2,8)=6,5
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4