Geometry 8

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by coolhabhi » Sun Jun 10, 2012 2:54 am
Image
In this problem suppose that the angle ACB is "z".
Now we know angle B is 90.
so x + (angle B) + z = 180
=> x + 90 + z = 180
=> x + z = 90---------->Eq 1

And at the point C, we have z + 55 + y = 180
=> z + y = 125--------->Eq 2

From Eq 1 and 2 we can say y = 35 + x
Answer A

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by coolhabhi » Sun Jun 10, 2012 2:59 am
Image

In this problem if the two lines are parallel then we can say the following:

C = 60 and angle A = angle B

So only option D is correct. But however I do have my doubts.

What is the OA?

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by coolhabhi » Sun Jun 10, 2012 3:07 am
Image

From the image you can say 30 + 30 + x + x + y + y = 180
=>2x + 2y = 120
=> x + y =60

and also is given that 2x = 2(2y)
=>x = 2y

Now substituting in the first equation, we get:
3y = 60
=>y = 20 and x = 40.

Now x - y = 20.

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by vickythakre » Sun Jun 10, 2012 7:44 am
Option C is correct.


coolhabhi wrote:Image

In this problem if the two lines are parallel then we can say the following:

C = 60 and angle A = angle B

So only option D is correct. But however I do have my doubts.

What is the OA?

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by ankita1709 » Sun Jun 10, 2012 10:30 pm
coolhabhi wrote:Image

From the image you can say 30 + 30 + x + x + y + y = 180
=>2x + 2y = 120
=> x + y =60

and also is given that 2x = 2(2y)
=>x = 2y

Now substituting in the first equation, we get:
3y = 60
=>y = 20 and x = 40.

Now x - y = 20.
It is nowhere given that POV line in a straight line..
Ankita