CBSE class 10 math-triangles facts
BPT (basic proportionality theorem) or Thales theorem. : If a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, the other two sides are divided in the same ratio
BPT (converse) : If a line divides two sides of a triangle in the same ratio, the line is parallel to the third side
Areas of similar triangles ( relation) : The ratio of the areas of two similar triangles is equal to the square of the ratio of their corresponding sides
Pythagoras theorem : In a right triangle, the square of the hypotenuse is equal to the sum of squares of the other two sides
Congruent figures are similar but : Similar figures are not congruent
Similarity of polygons: : Two polygons having game number of sides are similar if: (1) their corresponding sides are proportional i.e, in the same ratio(2) their corresponding angles are equal