Question

What is the radius of a circle whose equation ?????

Answer 1

`r = \sqrt{ L^(2) + K^(2) -C} = \sqrt{ (-4)^(2) + (3)^(2) - 21 } = √(4) = 2`

where L is negative half the coefficient of x and K is negative half the coefficient of y and c is the term free of x and y