-7+2(7х-2)=10
-7+14х-4=10
14х=10+7+4
х=1 1/2
-7-2(5х-6)=-2
-7-10х-12=-2
-10х=-2+7+12
х=-1 7/10
-2=-9-2(-2х+1)
-2=-9+4х-2
4х=-2+9+2
х=2 1/4
X^3 -2x² -8x =0
x(x² -2x -8) =0
x1=0
x² -2x -8 =0
D =4 +4*8=36=6²
x2 =(2 -6)/2 = -2
x3 =(2+6)/2 =4
ответ: x = -2; x =0; x =4
1,44-0.25=1,19
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