Question 827445
x^2+y^2=23

x-y=x=y+2

(y+2)^2+y^2=23

y^2+4y+4+y^2=23

2y^2+4y-19=0

/2
y^2+2y-19/2=0

y^2+2y+1-1-19/2=0

(y+1)^2= 21/2

y+1= +/- sqrt(21/2)

y= -1 +/-{{{sqrt(21/2)}}}