a)5,48++4,4x<9,92
4,4x<9,92-5,48
4,4x<4,44
x<4,44:4,4
x<1
x∈{0}
b)11,49+5,8x>17,3
5,8x>17,3-11,49
5,8x>5,81
x>5,81:5,8
x>1
x∈{2,3,4,5,6,....}
c)47,2-8,6x>38,56
8,6x>38,56+47,2
8,6x>85,76
x>85,76:8,6
x>9,97
x∈{10,11,12,13,14...}
d)7,94-0,7x<7,23
0,7x<7,23+7,94
0,7x<15,17
x<15,17:0,7
x<21,67
x∈{0,1,2,3,4,5,6....,20}