All rhombus are parallelogram.

In the given figure, $ABCD$ is a rhombus in which $\angle c=60°$, then $AC:BD$ will be

A rectangle with $12 \mathrm{cm}$ and $4 \mathrm{cm}$, reformed into a Rhombus. Both diagonals of Rhombus are equal and one of its angle is ${60}^{\mathrm{o}}$. Find the Area of Newly formed Rhombus.

The sides of a rhombus are $5 \mathrm{cm}$ each and one diagonal is $8 \mathrm{cm}$. If the area of the rhombus is $k {\mathrm{cm}}^2$, then find the value of $k$.

The sides of a rhombus are $5 \mathrm{cm}$ each and one diagonal is $8 \mathrm{cm}$. If the length of the other diagonal is $k \mathrm{cm}$, find the value of $k$.

$PQRS$ is a rhombus$:$

It is given that $PQ=3 \mathrm{cm},$ if the perimeter of $PQRS$ is $k \mathrm{cm}$, then find the value of $k$.

Diagonals of a parallelogram intersect each other at point $\mathrm{O}$. If $AO= 5$, $BO=12$ and $AB=13$ then, show that quadrilateral $ABCD$ is a rhombus.