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2014-10-09T14:35:03+03:00
A)-8x+4=-2
-8x=-6 ⇒ x= \frac{6}{8} =  \frac{3}{4}

b)-4x=-2⁴
-4x=-16
x=4

c)-3x+21=5²-1
-3x+21=25-1
-3x+21=24
-3x=3 ⇒ x=-1

d)|x|=9
x∈{9;-9}

e)|x|=-2
x∈∅

f)|x-1|=4
x-1∈{4;-4}
x∈{5,-3}

g)|x|=x
x∈{1,2,3,....}

h)|x|=-x
x∈∅











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