X^2-2xy+y^2=49
x-3y=1
x^2-2xy+y^2=49
x=3y+1
(3y+1)^2-2(3y+1)*y+y^2=49
y= -4 и 3
y = -4
x^2-2x(-4)+(-4)^2=49
x^2-2x(-4)+16=49
x^2-2x*(-4)+16=49
x^2+8x+16=49
x^2+8x-33=0
(x^2-3x+11x-33)=0
((x^2-3x)+(11x-33))=0
(x(x-3)+11(x-3))=0
(x+11)(x-3)=0
x+11 = 0 x -3=0
x= -11 x=3
=> x1 = -11 и x2 = 3
y=3
x^2-2x(3)+(3)^2=49
x^2-2x(3)+9=49
x^2-2x*3+9=49
x^2-6x+9=49
x^2-6x-40=0
D= (-6)^2-4*1*(-40)=196
x1,x2=> 6+-4/2 =
x1 = -4 и x2 = 10
Ответ: (-11,-4)(10,3)