if the diagonals of a quadrilateral are equal and bisect each other at right angle, then quadrilateral is ?
a. rectangle
b. parallelogram
c. rhombus
d. trapezium
Answers
Answer:
ᴛʜᴇ ǫᴜᴀᴅʀɪʟᴀᴛᴇʀᴀʟ ɪs ᴀ ʀʜᴏᴍʙᴜs.
Answer:
c. Rhombus.
Step by Step explanation:
Consider a rhombus ABCD and let its diagonals AC and BD intersect at O
Consider triangle AOB and triangle BOC
In these two triangles,
AB = BC [Sides of a rhombus]
BO = BO [Common Side]
AO = CO [Rhombus is a parallelogram, and the diagonals of a parallelogram bisect each other]
So, triangles AOB and BOC are congruent
So, their corresponding angles and equal
Thus, angle AOB = angle BOC
= x (say)
AOC is a straight line
So, by linear pair property,
angle AOB + angle BOC = 180°
=> x + x = 180° => x = 90°
Thus angle AOB = angle BOC = 90°
It can also be be proved that angle COD = angle AOD = 90° using the same mentioned steps
Thus we get angle AOB = angle BOC = angle COD = angle AOD = 90°
that is, diagonals of a rhombus bisect each other at right angles.
HOPE THIS HELPS...