1)
8(х-1,4)=0,56
8x-11.2=0,56
8x=0,56+11,2
8x=11,76
x=11,76:8
x=1,47
=======
2)
(4,6-х) *19=4,18
87,4-19x=4,18
19x=87,4-4,18
19x=83,22
x=83,22:19
x=4,38
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3)
(51,32+х)* 0,12=72
51,32+x=72:0,12
51,32+x=600
x=600-51,32
x=548,68
==========
4)
17,28 : (56-х)=36
56-x=17,28:36
56-x=0,48
x=56-0,48
x=55,52
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