4/25-6/100=16/100-6/100=10/100=1/10
2/5:14/100=2/5*100/14=20/2=10
<span>а) (x-3)^2-x(x+2.7)=9
x</span>²-6x+9-x²-2.7x=9
<span>-8.7x=0
x=0
б) 9y^2-25=0
(3y-5)(3y+5)=0
y</span>₁=5/3=1 2/3
y₂=-5/3=-1 2/3
-(5n-2(8n-4))-11n=-(5n-16n+8)-11n=-5n+16n-8-11n=-16n+16n-8=-8
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