A point Of is taken inside a quadrilateral ABCD such that it's distances from the angular points D and B are equal. Show that OA and OC are in one and same straight line.
Question is like this
a point O is taken inside an equilateral four sided figure ABCD such that its distances from the angular points D and B are equal. show that AO and OC are in one and the same stright line
Given : A point O is taken inside an equilateral quadrilateral ABCD such that DO = BO
To prove: AO and CO are in one and the same straight line
Proof: In
AD = AB (Given equilateral quadrilateral)
AO = AO (common)
OD = OB (Given)
Hence,
Therefore , angle AOD = angle AOB ……………..(1)
Similarly ,
Angle CDO = angle BOC ……………...(2)
But, angle AOD + angle AOB + Angle CDO + angle BOC = 360
2 angle AOB + 2 angle BOC = 360 (From eqn (1) and (2) )
2 (angle AOB + angle BOC )= 360
angle AOB + angle BOC = 180
Hence their outer arms AO and OC are in same and straight line
Hence proved
Figure cant be drawn
so please draw fig and lokk through this