Question

x² + y2 + 4x – 2y = -1
The equation of a circle in the xy-plane is shown
above. What is the radius of the circle?
A) 2
B) 3
C) 4
D) 9​

Answer 1

Answer:

(2)

Step-by-step explanation:

Given equation is x²+y²+4x -2y +1 = 0

Centre of the Circle = (-g, -f) = (-2, 1)

Radius of the Circle = √g²+f²-c

= √(-2)²+(1)²-1) = √4+1-1 = √4 = +-2

Option (A) 2 is correct answer