GEOMETRY,TRIANGLE ,CONCEPT OF SIMILARITY, THALES THEOREM, SIMILAR TRIANGLE AND THEIR CHARACTERISTIC PROPERTIES, PYTHAGORAS THEOREM, TANGENT TO A CIRCLE, 1OTH KA GEOMETRY CHAPTER (KNOWLEDGE IS THE BEST FRIEND. AN EDUCATED PERSON GETS RESPECT EVERY WHERE )BY:SUJEET SIR 8340763695,ARARIA ,BIHAR.