1) 20,6-(-7,9)=20,6+7,9=28,5
2) 3,8-4,4=-(4,4-3,8)=-0,6
3) -16,7-5,5=-(16,7+5,5)=-22,2
4) -2,2-(-15,1)=-2,2+15,1=15,1-2,2=12,9
5) 5/18 - 11/12= 10/36 - 33/36=-(33/36-10/36)=-23/36
6) -13/24 - 7/16= -(26/48+21/48)=-47/48
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8.96+x=4,18
x=4,18-8,96
x=-4,78
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y- 5 3/4=-6 5/8
y=-6 5/8+5 3/4
y=-(6 5/8-5 6/8)
y=-7/8