Parallelogram

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Parallelogram

by goyalsau » Wed Oct 27, 2010 9:56 am
Pretty much confused,
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by shovan85 » Wed Oct 27, 2010 10:30 am
goyalsau wrote:Pretty much confused,
Dude I am getting Perimeter as 240 :(
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by goyalsau » Wed Oct 27, 2010 10:36 am
This is solution that they have given, I just don't understand it,
it has to be 240
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by sixpointer » Wed Oct 27, 2010 10:36 am
can u explain the sign DSTU ?

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by shovan85 » Wed Oct 27, 2010 11:48 am
goyalsau wrote:This is solution that they have given, I just don't understand it,
it has to be 240
No man!! 96 is correct. we are comparing the wrong sides. We could know that both are similar but different angles are compared.
See the ratios and check the angles with respect to that you can get it.
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by shovan85 » Wed Oct 27, 2010 11:49 am
sixpointer wrote:can u explain the sign DSTU ?
Thats Angle STU ;)

Please provide that PNC solution there ... I have gone Crazy :(
5 days to go
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by Taniuca » Wed Oct 27, 2010 5:06 pm
I got the answer or 240.
From what I see how the similar triangles were compared doesn't make sense.

I used

PS: ST Like SR: SU

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by fskilnik@GMATH » Thu Oct 28, 2010 3:11 am
Hi there,

I have to teach in some minutes, so I will give the "key", if needed anything else to understand, please write and when I finish I come back.

Regards,
Fabio.

From the similarity of triangles (angle S common, the other is the given in the question stem...) we get:

x over (4x) = 4x - (x+20) over 2x

For me x is the length of PT (and ST) ... please have a look and I hope you understand.

The answer is x = 8 then 12x equals 96!!

Hint in general for similarity: look angles opposing sides, then you will know which side must be proportional to which side... I hope you got it. I must teach now!
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by goyalsau » Thu Oct 28, 2010 5:15 am
fskilnik wrote:Hi there,

I have to teach in some minutes, so I will give the "key", if needed anything else to understand, please write and when I finish I come back.

Regards,
Fabio.

From the similarity of triangles (angle S common, the other is the given in the question stem...) we get:

x over (4x) = 4x - (x+20) over 2x

For me x is the length of PT (and ST) ... please have a look and I hope you understand.

The answer is x = 8 then 12x equals 96!!

Hint in general for similarity: look angles opposing sides, then you will know which side must be proportional to which side... I hope you got it. I must teach now!
I think i got it now,
One more thing i like Now i know for similar two angles must be same,
is there any other property of similar triangles
Saurabh Goyal
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by fskilnik@GMATH » Thu Oct 28, 2010 5:38 am
goyalsau wrote: I think i got it now,
One more thing i like Now i know for similar two angles must be same,
is there any other property of similar triangles
I´m glad that I helped... as far as another similarity properties are concerned... I guess I detailed all (GMAT-related) important facts about it in an online GMATH material of mine called "Express Class #4"... so that I invite you to go there, register and meet my online course! (Sorry for the advertising... but it´s the best material I know on this matter, if you allow me not be humble...) ;)
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
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Portuguese-speakers :: https://www.gmath.com.br