CBSE Class 9 Maths Triangles
 be and CF are two traiangle equal altitude of triangle abc using rhs congruence rule prove that the triangle abc is isosceles

in an isosceles triangle ABC with AB=AC, the bisectors of angleB and angle C intersect each other at o. Join A at O. show that Ob= OC that
 How to proove RHS congruence
 In the given figure, BAAC and DEEF such that BA = DE and BF = DC. Prove that AC = EF.
 ABC is an isosceles triangle with AB = AC. Bisectors of B and C intersect at O. Prove that BO = CO and AO bisects BAC.
 ABCD is a square, X and Y are the points on the sides AB and DC respectively such that BY = CX. Prove that CY = BX and CBY = BCX.
 In an isosceles triangle, prove that the altitude from the vertex divides the triangle into two congruent triangles..
 AD is the median of ABC. If BL and CM are drawn perpendiculars on AD produced, prove that BL= CM.
 If two isosceles triangles have a common base, then the line joining their vertices bisects the base at right angles.
 A point O is taken inside an equilateral four sided figure ABCD such that its distances from the angular points D and B are equal. Show that AO and OC are in one and the same straight line.