(-2/3)³-1= -8/27-1= -1 8/27
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(-2*(-2)*(-2))/(3*3*3)= -8/27 - возвели дробь в 3-ю степень
-8/27-1= -1 8/27
<span>(а-3)x=8
</span><span>(а-3)*4=8
4а-12=8
4а=8+12
4а=20
а=20/4
а=5
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<span>2,5 (3,6-x) = 2,4(5,2-x)
2,5*3,6 -2,5х = 2,4*5,2 -2,4х
9-2,5х = 12,48-2,4х
-2,5х+2,4х=12,48-9
-0,1х=3,48
х= 3,48:(-0,1)
х= - 34,8
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