This is an interesting angle because most people searching for "Mathematics Form 4 textbook answer" are usually looking for a PDF or a quick solution. A review of the answer scheme itself—not the textbook—is quite meta.

Here is an of a typical "Mathematics Form 4 Textbook Answer" (assuming the Malaysian KSSM syllabus), written from the perspective of a discerning student or tutor. Review Title: The Answer is Just a Number. The Scheme is the Teacher. Rating: ⭐⭐⭐☆☆ (3/5)

You just finished a page of quadratic inequalities. You flip to the back. There it is: "Answer: -1 < x < 4" . No steps. No "why." Just the final, naked truth.