arifaisal wrote:

In the diagram above, AB=CD, From this we can deduce that: A) AB is parallel to CD. B) AB is perpendicular to?

In the diagram above, AB=CD, From this we can deduce that:

A) AB is parallel to CD.

B) AB is perpendicular to BD.

C) AC=BD

D) Angle ABD equals angle BDC.

E) Triangle ABD is congruent to triangle ACD

Picture reference:

http://www.pagalguy.com/forums/gmat-and ... /r-2577147Please explain in details and simple words, im not getting it from the other site.

All we know is that AB = CD. It is possible that AB and CD are slightly tilted (exaggerated in the diagram below). What seems to hold from the diagram may not actually hold. It looks like a square but the info given doesn't substantiate it. All we can say is that AB = CD. We don't know whether AC = BD.

Attachment:

Ques3.jpg [ 7.15 KiB | Viewed 726 times ]
A) AB is parallel to CD.

Not necessary. Obvious from the diagram.

B) AB is perpendicular to BD.

Not necessary. Obvious from the diagram.

C) AC=BD

Not necessary. Obvious from the diagram.

D) Angle ABD equals angle BDC.

arc AB = arc CD (Since segment AB = segment CD, the arcs should be equal too)

arc CAB = arc ACD (obtained by adding arc AC to both above)

arc CAB subtends angle BDC.

arc ACD subtends angle ABD.

Since the two arcs are equal, the angles they subtend are equal too.

So angle ABD = angle BDC

E) Triangle ABD is congruent to triangle ACD

Not necessary.

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