Question

if the diagonals of a parallelogram intersect at right angle. prove that it is a rhombus.. plzz solve it fast today evng is my tution.

Answer 1

 GIVEN:a parallelogram ABCD in which daigonals AC and BD intersect at right angle at O 
TO PROVE: ABCD is a rhombus 
PROOF: IN  TRIANGLE AOD and AOB 
OA=OA (COMMON)
<AOD= <AOB =90
TRIANGLE AOD IS CONGRUENT TO TRIANGLE AOB BY (RHS CONGRUENCY)
AD=AB (CPCT)
SIMILARLY     AB=BC=CD=DA