The equation x2 + y2 − 2x + 2y − 1 = 0 is the general form of the equation of a circle. What is the standard form of the equation?

Answer 1

x^2 + y^2 − 2x + 2y − 1 = 0 , notice how we indicate exponents

complete the square

x^2 + y^2 − 2x + 2y = 1
x^2 - 2x + 1 + y^2 + 2y + 1 = 1+1+1

(x-1)^2 + (y+1)^2 = 3