The quadrilateral formed by joining the mid-points of the sides of a quadrilateral PQRS, taken in order, is a rhombus, if
(A) PQRS is a rhombus
(B) PQRS is a parallelogram
(C) diagonals of PQRS are perpendicular
(D) diagonals of PQRS are equal.
Answer: [D]
Solution.
According to question, the quadrilateral ABCD is formed by joining the midpoints of PQRS
If PQRS is a rhombus
Here ABCD is not a rhombus because in rhombus angles need not be right angles.
But here
ABCD is a square not a rhombus.
If PQRS is a parallelogram
Here ABCD is not a rhombus because in rhombus all sides of if will be equal here sides of quadrilateral ABCD are not equal
it is not a rhombus
If diagonals of PQRS are perpendicular
Here AB D is not a rhombus because in rhombus angles are not right angles and all sides are equal but here AB = CD and BC = AD also
Hence ABCD is a rectangle not a square.
If diagonals of PQRS are equal
In ABCD quadrilateral here all sides are equal and angles of quadrilateral ABCD is not right angle, therefore, ABCD is a rhombus\
\ option D is correct
(D) diagonals of PQRS are equal