Geometry (Triangle)

**lsv** · 01-14-2007, 06:58 AM

AE = ED , FD = BF. Side AB = 6 cms
If perimeter of quadrilateral EDFB is 6√2. What is the perimeter of ABC.

**thankont** · 01-14-2007, 01:00 PM

Are tou sure that the side AB = 6 and not AC = 6 since if AC was 6 then
length of perimeter of quadr. is equal to the length of the other 2 sides
and then perimeter of tr. would be 6+6sqrt(2)
wishful thinking!!!
thanx

**lsv** · 01-14-2007, 01:07 PM

Originally Posted by thankont

Are tou sure that the side AB = 6 and not AC = 6 since if AC was 6 then
length of perimeter of quadr. is equal to the length of the other 2 sides
and then perimeter of tr. would be 6+6sqrt(2)
wishful thinking!!!
thanx

Oh, it could very well be. One of these pbs I found on the net.. However, pl post your procedure.. Thanks

**thankont** · 01-14-2007, 01:19 PM

BE + ED + DF + FB = (BE + EA) + (CF +FB) since EA = ED and FD = FC so
AB + BC = 6*sqrt(2) and perimeter = 6 + 6*sqrt(2)
(this soln. is based on the assumption that AC = 6 and not AB = 6
as the problem states)
thanx

**lsv** · 01-14-2007, 01:23 PM

Originally Posted by thankont

BE + ED + DF + FB = (BE + EA) + (CF +FB) since EA = ED and FD = FC - Why ?so
AB + BC = 6*sqrt(2) and perimeter = 6 + 6*sqrt(2)
(this soln. is based on the assumption that AC = 6 and not AB = 6
as the problem states)
thanx

How does FD = BD give FD = FC ? I'm sorry if the qn is basic..but I just didnt get it

**thankont** · 01-14-2007, 01:26 PM

ISV you are correct I misplaced letters so what I wrote is wrong.
I will see it again...
thanx

**MikeJung** · 01-22-2007, 08:41 PM

what s the Official Answer?

**asdada1** · 01-23-2007, 12:04 AM

Originally Posted by thankont

Are tou sure that the side AB = 6 and not AC = 6 since if AC was 6 then
length of perimeter of quadr. is equal to the length of the other 2 sides
and then perimeter of tr. would be 6+6sqrt(2)
wishful thinking!!!
thanx

no it wont be it would be 6root2+6+AE+FC

**asdada1** · 01-23-2007, 12:04 AM

i think it would help if the triangle was given as eq triangle

i solved a bit

ae = ed = x
df=bf=y
bedf = 6root2 --- 1
AB=6 implies be=6-x --- 2

from 1 and 2
2y+x+(6-x) = 6root2
hence y=3root3

form here on we need to know if the triangle is a equilateral triangle based on that we can equate x and y and polish off things else its a toughie