Preface MATHEMATICS POWER FOR SECONDARY SCHOOLS (MPSS) series are specially written for secondary school learners, developing the four years secondary school mathematics course. Book 1 is the first book in the series and it is specially for learners in their first year of secondary school. Other readership involving secondary school teachers, tutors and learners in Teacher Training Colleges (for both primary and secondary schools), Technical schools and institutes, etc. may find the series selectively important to their learning or class work preparations. Finally, adult learners who wish to further their knowledge in secondary school mathematics may too find the series important to them. The purpose of the series is to provide a well structured approach in numerical and analytical secondary school mathematics knowledge and skills. The organization and presentation is such that all the work is logical, coherent, comprehensive and objectively handled to equally cater for the average and the more able students. In a systematic manner using clear instructional language for explanatory notes, worked out examples, illustrations, tables, figures, etc. the book allows the reader sufficient involvement in mathematical reasoning, convenient work rate, comprehension, and to stimulate interest in the subject being studied. The concepts are related to real life experiences in order to enhance their methodical treatment as much as possible. For the learners' practice and assessment, brain storming trial questions, graded exercises, revision exercises and examination type papers are provided. Suleiman Luutu Namielus Educational