Question

Show that if the diagonals of a quadrilateral bisect each other at right angles, then it
is a rhombus.​

Answer 1

The diagonals are AC and BD

Let the diagonals bisect each other at O.

In ΔAOBandΔAOD

OA=OA (common)

OB=OD (given the bisect)

∠AOB=∠AOD (each 90

0

)

∴ΔAOB≅ΔAOD (SAS criteria)

The corresponding parts are equal.

AB=AD

Similarly, AB=BC

BC=CD

CD=AD

∴AB=BC=CD=DA

i.e. the quadrilateral is a Rhombus

Answer 2

Step-by-step explanation:

Take quadrilateral ABCD , AC and BD are diagonals which intersect at O.

In △AOB and △AOD

DO=OB ∣ O is the midpoint

AO=AO ∣ Common side

∠AOB=∠AOD ∣ Right angle

So, △AOB≅△AOD

So, AB=AD

Similarly, AB=BC=CD=AD can be proved which means that ABCD is a rhombus.