Find the equation of the set of points which are equidistant from (3,10) and the x-axis. a. y=1/5 (x-5)^2 + 3 b. y-10=20(x-3)^2 c. y=1/20 (x-3)^2 + 10 d. y=1/10(x-3)^2 + 5