Question

the circle below is centered at (-1,1) and has a radius of 3. what is its equation?

Answer 1

Answer:

$(x+1)^2 + (y-1)^2 = 9\\\\or\\\\x^2 + y^2 +2x -2y -7 = 0$

Step-by-step explanation:

$(x +1 )^2 + (y -1)^2 = 3^2\\\\x^2 +2x +1 + y^2 + 1 -2y = 9\\\\x^2 + y^2 +2x -2y +2 -9 = 0\\\\x^2 + y^2 +2x -2y -7 = 0$