Question

Решите систему уравнений {x-y=1, {x-4y(В квадрате)=1.

Answer 1

x-y=1

x-4y^2=1

 

x-y=1

y=x-1

x-4y^2=1

x-4*(x-1)^2=1

9x-4x^2-5=0

D=9^2-4*(-4)*(-5)=81-80=1

x1=(1-9)/(2*(-4))=1
x2=(-1-9)/(2*(-4))=1.25

x-y=1

 

1-y=1

y1=0

 

1.25-y=1

y2=0.25