Final answer:
The provided details seem unrelated to the mathematical expression given, making it impossible to answer confidently.
Step-by-step explanation:
The provided information in the question does not explicitly lead to a clear mathematical problem regarding the expression (a + 29) (a - 23) 42. The additional solutions and formulas supplied appear to be unrelated to the initial expression and seem to pertain to various mathematical contexts such as quadratic equations and other algebraic problems. Without a direct connection to the original expression or a clear question, it is impossible to provide a correct answer or a step-by-step explanation. It is recommended that the student clarifies the question, ensuring they provide all necessary information for the expression (a + 29) (a - 23) 42.