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705-805 (Hard)|   Geometry|      
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Bunuel
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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 08:15
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C
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Difficulty:

75% (hard)

Question Stats:

36% (01:28) correct 64% (01:06) wrong based on 98 sessions

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Is a = b ?

(1) x = y
(2) c = x

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2021-09-15_15-31-47.png
2021-09-15_15-31-47.png [ 5.29 KiB | Viewed 2433 times ]
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C
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gloriasc
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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 08:18
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Where is b ? I can’t find it in the graph!

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Bunuel
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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 08:20
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gloriasc
Where is b ? I can’t find it in the graph!

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d there in the image should have been b.
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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 08:32
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Only 2 is sufficient.

If x = c, it means that the angles are 90\(^{\circ}\)

From statement 1 though, we can ascertain x = y = 90\(^{\circ}\)
But we can not say anything of the bottom line and angles c and b associated with it. Hence, insufficent.

So, option B is correct according to me.
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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 08:45
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Correct Option D
Both statement are sufficient to answer the problem

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Is a = b ? (1) x = y (2) c = x 06 Oct 2021, 09:33
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100mitra
Correct Option D
Both statement are sufficient to answer the problem

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It is not given that both the lines are parallel. It seems you just assumed them to be true without that information being explicitly mentioned in the question.
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Is a = b ? (1) x = y (2) c = x 12 Jul 2022, 00:03
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PyjamaScientist
Only 2 is sufficient.

If x = c, it means that the angles are 90\(^{\circ}\)

From statement 1 though, we can ascertain x = y = 90\(^{\circ}\)
But we can not say anything of the bottom line and angles c and b associated with it. Hence, insufficent.

So, option B is correct according to me.
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If x = c, how can we conclude that all angles are 90? Its not given that two lines are parallel..
Can someone please explain?
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Is a = b ? (1) x = y (2) c = x 13 Jul 2022, 09:19
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Bunuel

Is a = b ?

(1) x = y
(2) c = x

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if 2 lines are parallel => a =b

(1) x = y
=> 2 horizontal lines are not sure parallel or not
=> Insuff

(2) c = x
=> 2 horizontal lines are not sure parallel or not
=> Insuff

(1) & (2) => the vertical line perpendicular to the 2 horizontal lines
=> a = b = 90 degrees
=> Suff

=> Choice C
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