This book has been written to broadly follow both the Australian and the NSW Advanced Year 9 Mathematics Curriculum (5.3). It is intended to be a very thorough and concise summary of most major core topics which are taught and covered in Year 9 Advanced classes throughout Australia. Please keep in mind that this curriculum is based on the work covered in 2 years of high school (Year 9 and Year 10) which implies that different schools may teach the topics in a different order throughout the two year period. Therefore if you cannot find a particular topic summary in this Year 9 book (for example: probability), then you will almost certainly find it explained in the Understanding Year 10 book. This book will prove to be very beneficial to students, teachers and coaches in all states. It has primarily been developed to be used as an additional learning aid to the conventional school text book, but it could also be used as a class text on its own account.