Lines and angles problem

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Lines and angles problem

by The Jock » Mon Jun 28, 2010 4:14 am
In the figure below, if lines k and m are parallel, what is the value
of x?
(1) z = 110
(2) y = z

Image

Why option 2 is insufficient here......
Thanks and Regards,
Varun
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by nathanalgren » Mon Jun 28, 2010 4:22 am
Because you don't even need option two to know y=z. If they are parallel, y=z.And the option 2 does not give you anything you don't already know. Therefore you cannot solve this question.

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by The Jock » Mon Jun 28, 2010 4:25 am
Hey nathanalgren,

Thanks a lot.
Thanks and Regards,
Varun
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by nathanalgren » Mon Jun 28, 2010 4:27 am
The Jock wrote:Hey nathanalgren,

Thanks a lot.
You are welcome. If it said x=z or x=y, then you could solve it and the answer would be 90.

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by raunakrajan » Mon Jun 28, 2010 5:21 am
how would it be 90 could you pls explain!

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by nathanalgren » Mon Jun 28, 2010 5:24 am
raunakrajan wrote:how would it be 90 could you pls explain!
Because of that the lines are parallel, x+z and x+y are equal to 180 (straight line is 180 degrees). So if x=z or x=y, insert them into the equations and you get 2x=180 and x=90.

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by raunakrajan » Mon Jun 28, 2010 5:27 am
thanks! silly doubt.. was thinking about the value of z as 110 hence

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by Haaress » Mon Jun 28, 2010 7:58 am
You're correct that the answer is A, however, the Angle x is not 90 degrees, but rather it is 70 degrees. Z and Y have the the same angle degree because they are alternate exterior angle. Thus the Z and X are supplementary angles and add up to 180 degrees.

Hope that helps!

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by nathanalgren » Mon Jun 28, 2010 7:59 am
Haaress wrote:You're correct that the answer is A, however, the Angle x is not 90 degrees, but rather it is 70 degrees. Z and Y have the the same angle degree because they are alternate exterior angle. Thus the Z and X are supplementary angles and add up to 180 degrees.

Hope that helps!
That is for option 1. We were talking about something else.

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by Ritwik » Tue Jun 29, 2010 1:52 pm
answer should be D !!! y=z means x=90.