Geometry problem

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Geometry problem

by The Jock » Tue Jun 29, 2010 2:41 am
In the figure below, segments RS and TU represent two
positions of the same support beam leaning against the
side SV of a structure. The length TV is how much greater
than the length RV ?
(1) The length of SU is 2underroot2 - 4 meters.
(2) The ratio of the length of V R to V T is underroot6 : 2.


Image

I know that the given triangles are 45:45:90 and 30:60:90 triangles. But I need some more explanation...
Thanks and Regards,
Varun
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by nathanalgren » Tue Jun 29, 2010 4:09 am
Is the answer only 1?

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by The Jock » Tue Jun 29, 2010 5:06 am
Yes...
Thanks and Regards,
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by nathanalgren » Tue Jun 29, 2010 5:11 am
The Jock wrote:In the figure below, segments RS and TU represent two
positions of the same support beam leaning against the
side SV of a structure. The length TV is how much greater
than the length RV ?
(1) The length of SU is 2underroot2 - 4 meters.
(2) The ratio of the length of V R to V T is underroot6 : 2.


Image

I know that the given triangles are 45:45:90 and 30:60:90 triangles. But I need some more explanation...
Okay the lengths SR=UT and suppose they are equal to 2x.squareroot6. (for easier calculations)
So 45-45-90 triangle gives us; UV=VT=2x.squareroot3
30-60-90 triangle gives us; VR=x.sqaureroot6 and SV=3x.squareroot2.

So all we need to know is x. Then we can find the length of any line in this image. Using Option (1), we can find X because we know SV and UV,but option (2) does not give us anything we dont know. Because we already know the ratio of VR to VT.

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by mj78ind » Tue Jun 29, 2010 5:50 am
The Jock wrote:In the figure below, segments RS and TU represent two
positions of the same support beam leaning against the
side SV of a structure. The length TV is how much greater
than the length RV ?
(1) The length of SU is 2underroot2 - 4 meters.
(2) The ratio of the length of V R to V T is underroot6 : 2.


Image

I know that the given triangles are 45:45:90 and 30:60:90 triangles. But I need some more explanation...
@Nathan and Jock

The logic used by Nathan looks spot on. I have one issue though, 2sqrt2 - 4 per stmt 1 is a negative number hence the numbers need to be relooked at.......