![\left \{ {{2x+y=-1} \atop { x^{2} +2y=3}} \right.](https://tex.z-dn.net/?f=+%5Cleft+%5C%7B+%7B%7B2x%2By%3D-1%7D+%5Catop+%7B+x%5E%7B2%7D+%2B2y%3D3%7D%7D+%5Cright.+)
\
y=-1-2x
![x^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+)
+(-2-4x)=3
![x^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+)
-4x-5=0
D=16+20=36
x1=(4+6)/2=5
x2=(4-6)/2=-1
y1=-1-(2*5)=-11
y2=-1-((-1)*2)=1
2)
{ x^{2} - 2xy + y^{2} =16
{x+2y =11
{
![x^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+)
+ 2y =3 (типа тоже с ними)
x=11-2y
![x^{2} - 2xy + y^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+-+2xy+%2B+y%5E%7B2%7D+)
= (x - y)²
(11-2y-y)
![^{2}](https://tex.z-dn.net/?f=+%5E%7B2%7D+)
=16
105-66y+9y²=0
D=4356 - 3780 = 576
y1=(66+24)/210=3/7
y2=(66-24)/210=0.2
x1=11-6/7
x2=11-0.4=10.6
3)
![\left \{ {{x+y=-2} \atop {5x-3y=3}} \right.](https://tex.z-dn.net/?f=+%5Cleft+%5C%7B+%7B%7Bx%2By%3D-2%7D+%5Catop+%7B5x-3y%3D3%7D%7D+%5Cright.+)
метод сложения:
8x=-3
x=-3/8
Вроде бы все по правилам.
M ≈ -0.8
1) √6-m = √6+0.8= √6.8 ≈ 2.607, т.е. точка С
2) m^2 = (-0.8)^2= 0.64, т.е. точка B
3) m-1 = -0.8-1≈-1.8, т.е. точка А
4) -3/m - оставшаяся точка D
D = 85
S16 = s6 + 10d
S16 = 57 + 850
S16 = 907