<span>x^2-11x+24≥0
x1+x2=11 U x1*x2=24
x1=3 x2=8
+ _ +
---------------[3]---------------[8]---------------
x</span>∈(-∞;3] U [8;∞)
ΔABC,AB=BC
cos<A=0,2
BH_|_AC
<ABH=90-arccos(0,2)
sin<ABH=sin(90-arccos0,2)=cos(arccos0,2)=0,2⇒<ABH=arcsin0,2
<B=2<ABH=2arcsin0,2
4,2х-(3,4х+4)=7-(8-1,2)
4,2х-3,4х-4=7-8+1,2
4,2х-3,4х=7-8+1,2+4
0,8х=4,2
х=4,2/0,8
х=5,25
3(0.9-1)-(х+0.6)=-0.2
2.7-3-х-0.6=-0.2
х=-0.2+2.7-3-0.6
х=-0.7
х=-0.7
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