These platforms often host step-by-step solutions for Sadiku’s 4th and newer editions. While they require a subscription, the solutions are verified and the platforms are secure.
Most engineering departments keep physical copies of the Instructor’s Solution Manual (ISM) on reserve. Check your campus library’s reference section.
To truly succeed in your EM course, use the solution manual only as a last resort to check your work. Focus on mastering the foundations in the first three chapters of Sadiku, as those tools are the "language" used for the rest of the book.