The figure obtained by joining the mid-points of the adjacent sides of a rectangle of sides 8 cm and 6 cm is :
(A) a rectangle of area 24 cm2
(B) a square of area 25 cm2
(C) a trapezium of area 24 cm2
(D) a rhombus of area 24 cm2
Answer: [D]
Solution.
Let ABCD be a rectangle.
Given sides 8 cm and 6 cm.
Let length of rectangle = 8 cm
Breadth of rectangle = 6 cm
Let E, F, G and H are the mid-points of the sides of rectangle
AE = EB = DG = GC = 3 cm
AH = HD = BF = FC = 4 cm
Then we have to find out about the figure EFGH.
In , using Pythagoras theorem
So, EH = 5 cm.
Similarly we can find out HG = GF = FE = 5 cm
Hence EFGH is a rhombus.
Now, area of rhombus =
Where are the diagonals of the rhombus
area of rhombus =
Here, EG = AD = 8 cm
and HF = AB = 6 cm
\ Area of rhombus EFGH =
Therefore option (D) is correct.