Original sentence: In some other (less common) systems of units, such as CGS-Gaussian, many of these equations would be altered.The equation given above for the electric potential (and all the equations used here) are in the forms required by SI units
Edited sentence: In older systems of equations (thankfully now dropping out of use) different forms would be required for these equations.The equation given above for the electric potential  (and all the equations used here) are in the forms required by the (rationalized) metre-kilogramme-second-ampere system of equations that, since the 1970s, has been used as the basis for the modern International System of Quantities and SI units