<span>24,5\2,5;у = у=9,8</span>
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У=1,5х+2х=2у
У=2,5х=5у
У=7,5х
Точно не уверена
1.
1) =3
![x^{4}](https://tex.z-dn.net/?f=+x%5E%7B4%7D+)
-12x²+18x
2)=2x²-5x-3
3)=20a²-11ab-42b²
4)=y³+3y²-6y-16
2.
1)=5a(a-4b)
2)=7x³(1-2x²)
3)=3(a-b)+x(a-b)=(a-b)(x+3)
3.
4x²-12x=0
4x(x-3)=0
![x_{1} =0 x_{2} =3](https://tex.z-dn.net/?f=+x_%7B1%7D+%3D0+%C2%A0+x_%7B2%7D+%3D3)
4.
=6a²-10a-a²+10a-21=5a²-21
5.
![\frac{6x+27-2x+4}{12} =3 ](https://tex.z-dn.net/?f=+%5Cfrac%7B6x%2B27-2x%2B4%7D%7B12%7D+%3D3%0A)
![\frac{4x+31}{12}=3 ](https://tex.z-dn.net/?f=%5Cfrac%7B4x%2B31%7D%7B12%7D%3D3%0A)
4x+31=36
4x=5
x=5/4
2)2x²+11x-21=2x²+5x-12+3
6x=12
x=2