I'm going to assume you mean the following:
. . . . .\(\displaystyle \large{\frac{4}{2x\,+\,3}\, + \,\frac{17}{5x\,-\,3}\, = \,3}\)
One method for solving this equation would be to multiply through by the common denominator of (2x + 3)(5x - 3). Then solve the resulting quadratic equation.
Eliz.