We have,
x+y2−4y+5=0
y2−4y+4−4+x+5=0
(y−2)2+x+1=0
⇒(y−2)2=−(x+1)
Therefore, this is the standard form.
Find the equation of circle circumscribing the quadrilateral formed by four lines 3x + 4y − 5 = 0, 4x − 3y − 5 = 0, 3x + 4y + 5 = 0 and 4x − 3y + 5 = 0