Let C be the circle with equation x^2+2y-9=-y^2+18x+9+12x+22. If (a,b) is the center of C and r is its radius, what is the value of a+b+r?
x^2+2y-9=-y^2+18x+9+12x+22 => x2 + y2 - 30x + 2y - 40 = 0 => (x - 15)2 + (y + 1)2 = 266
Center ( 15, -1), radius r = \(sqrt{266}\)
