x-3y=1
2xy-x²+9y²=11-4x
x=1+3y
2y(1+3y)-(1+3y)²+9y²=11-4(1+3y)
2y+6y²-1-6y-9y²+9y²=11-4-12y
6y²+8y-8=0
3y²+4y-4=0
D=16+48=64
y1= (-4+8)/6= 2/3
y2= (-4-8)/6 = -2
x1= 1+3*2/3= 3
x2= 1-3*2= -5
ответ: (3;2/3), (-5;-2)
x-3y=1
2xy-x²+9y²=11-4x
x=1+3y
2y(1+3y)-(1+3y)²+9y²=11-4(1+3y)
2y+6y²-1-6y-9y²+9y²=11-4-12y
6y²+8y-8=0
3y²+4y-4=0
D=16+48=64
y1= (-4+8)/6= 2/3
y2= (-4-8)/6 = -2
x1= 1+3*2/3= 3
x2= 1-3*2= -5
ответ: (3;2/3), (-5;-2)