Perhaps, as a result, neither is given sufficient attention. Linear combinations are addressed in two sections, but even this much emphasis is not sufficient. References to properties of equality are not even given. No specific section on problem situations is provided and they are not handled sufficiently in the examples. Without this feature, the ability to apply the mathematics of this major topic is not well-supported.
Difficult problems are extremely rare.
Linear programming, matrix solutions, and 3 equations in 3 unknowns are not covered. The number of problems for specific subtopics is often extremely limited. Problems are almost always of an easy variety. Explanations are not sufficiently detailed. There are some activities that are not efficient uses of time in terms of the learning potential they possess.