Ineed finding the radius to this question:
circle o is represented by the equation (x+2)^2 + (y-5)^2=48.the coordinates of the center and the length of the radius of circle o

To find the center you would set (x+2) and (y-5) equal to 0. Solving for x and y, you get that x=-2 and y=5. Center: (-2,5). You can also think of this as solving for the additive inverse of 2 and -5. To find the radius, simply take the square root of 48, leaving you with 4√3. 
Remember the from is (x-h)²+(y-k)²=R² To find R just take the square root of the constant.