The general form of the equation of a circle is x2 + y2 + 42x + 38y − 47 = 0. the equation of this circle in standard form is a) (x - 21)^2 + (y - 19)^2 = 127
b) (x + 21)^2 + (y + 19)^2 = 849
c) (x + 21)^2 + (y + 19)^2 = 851
d) (x - 19)^2 + (y - 21)^2 = 2,209 .the center of the circle is at the pointa) (-19, -21) b) (-21, -19) c) (19, 21) d) (21, 19) , and its radius is a) 127^(1/2)b) 849^(1/2) c) 851^(1/2)d) 47 units.the general form of the equation of a circle that has the same radius as the above circle is a) x^2 + y^2 + 60x + 14y + 98 = 0 b) x^2 + y^2 + 44x - 44y + 117 = 0 c) x^2 + y^2 - 38x + 42y + 74 = 0 d) x^2 + y^2 - 50x - 30y + 1 = 0 .