Whether you buy the physical book or (legally) obtain a scanned copy from a library, here is the optimal study method for Birey B Geometri:
For every problem you cannot solve in the Birey B PDF, you must watch a video solution (available on YouTube via Birey's official playlists or third-party educators) and then re-solve it without looking. Birey B Geometri Pdf
Properties of special quadrilaterals like parallelograms and rhombuses. Whether you buy the physical book or (legally)