45c-3√625/5=75 what is the value of c

Need ! discuss how to convert the standard form of the equation of a circle to the general form. 50 points

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

There is an entrance to the computer room at point e which lies on ab and is 5 feet from point a. plot point e on the coordinate plane. find the distance from the entrance at point e to the printer at point e