Analytic approximations for synchrotron, synchrotron self-Compton (SSC), and external Compton (EC) processes are used to constrain model parameters for knot and hot-spot emission in extended jets of radio galaxies. Equipartition formulas are derived that relate the Doppler factor delta and the comoving magnetic field B assuming a nonthermal synchrotron origin of the radio emission and synchrotron, SSC, and EC origins of the X-ray emission. Expressions are also derived for d and B that minimize the total jet powers of the emitting region in synchrotron, SSC, and EC models for the X-ray emission. The results are applied to knot WK7.8 of PKS 0637 - 752. Predictions to test two-component synchrotron and EC models are made for Chandra and the Gamma-Ray Large Area Space Telescope.