Basic proportionality Theorem or Thales Theorem class 10th
Imp points or results used in Basic proportionality theorem or Thales theorem:- (i) Area of Triangle = 1/2 base* height Area of Triangle= 1/2 base*height =1/2 BC*AD (ii) Area of obtuse triangle = In this figure CM is height of the triangle and AB is the base Area of triangle = 1/2 base* height =1/2 AB* CM (iii) Two triangles on the same base (or equal bases) and between the same parallels are equal in areas. (class 9th) There are two triangle in this figure △CDA and △CDB so, ar(CDA)= ar(CDB) Theorem 6.1 if a line is drawn parallel to one side of triangle to intersect the other two sides in distinct points, the other two sides are divided in the same ratio . Proof Given:- triangle ABC in which a line l parallel to side BC intersects other two sides AB and AC at D and E respec...