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Re: Area of triangular region [#permalink]
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15 Dec 2013, 23:21
AccipiterQ wrote: I thought if you dropped a line down from a triangle vertex and it formed a right angle on the opposite side then that line bisected the side? So in this case if you know what BD is then you know what DC is?
To figure out whether it holds, why don't you try drawing some extreme figures, say, something like this: Attachment:
Ques3.jpg [ 3.67 KiB  Viewed 1239 times ]
Will this be true in this case? When will it be true? When the triangle is equilateral, sure. Also when the triangle is isosceles if the equal sides form the angle from which the altitude is dropped. Don't put your faith in the figure given. It may be just one of the many possibilities or may be somewhat misleading.
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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15 Dec 2013, 23:50
amitjash wrote: Attachment: Triangle.jpg If AD is 6 and ADC is a right angle, what is the area of triangular region ABC? (1) Angle ABD = 60° (2) AC = 12 Statement I is insufficient The left triangle becomes a 90 30 60 triangle however we don't know anything about the right triangle Statement II is insufficient The right triangle becomes a 90 30 60 triangle however we don't know anything about the left triangle Combining is sufficient We know both the triangles are 90 30 60 with same sides. Hence Answer is C Pushpinder Gill
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Re: Area of triangular region [#permalink]
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24 Jan 2014, 22:10
Hi Bunuel,
I have a question.
Can I not imagine that, in a right angled triangle if one of the side of a triangle bears x square root 3 as its length can I not imagine that it's a 306090? If not why.
Please help. Thanks Suneel



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Re: Area of triangular region [#permalink]
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25 Jan 2014, 03:39



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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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06 Feb 2014, 11:28
Bunuel wrote: manimgoindowndown wrote: Hey I had the same question as the last poster. How do we know that BD and DC are of the same length? or that angle BAC has been bisected? They are not equal: \(BD=\frac{6}{\sqrt{3}}\) (from the first statement) and \(AD=6*\sqrt{3}\) (from the second statement). I think answer is E, since it is not given that BDC points are collinear.



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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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07 Feb 2014, 05:27
virendrasd wrote: Bunuel wrote: manimgoindowndown wrote: Hey I had the same question as the last poster. How do we know that BD and DC are of the same length? or that angle BAC has been bisected? They are not equal: \(BD=\frac{6}{\sqrt{3}}\) (from the first statement) and \(AD=6*\sqrt{3}\) (from the second statement). I think answer is E, since it is not given that BDC points are collinear. That's not correct. OG13, page 272: A figure accompanying a data sufficiency problem will conform to the information given in the question but will not necessarily conform to the additional information given in statements (1) and (2). Lines shown as straight can be assumed to be straight and lines that appear jagged can also be assumed to be straight. You may assume that the positions of points, angles, regions, and so forth exist in the order shown and that angle measures are greater than zero degrees. All figures lie in a plane unless otherwise indicated. OG13, page 150: Figures: A figure accompanying a problem solving question is intended to provide information useful in solving the problem. Figures are drawn as accurately as possible. Exceptions will be clearly noted. Lines shown as straight are straight, and lines that appear jagged are also straight. The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All figures lie in a plane unless otherwise indicated. Hope it helps.
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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18 Mar 2014, 01:11
what if question wud have been like this.. If AD is 6, and ADC is a right angle, what is the area of equilateral triangle ABC?
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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18 Mar 2014, 08:51
sanjoo wrote: what if question wud have been like this..
If AD is 6, and ADC is a right angle, what is the area of equilateral triangle ABC? Then statement 1 would have been irrelevant and statement 2 would have been incorrect. If side of an equilateral triangle is 12, the altitude would be \((\sqrt{3}/2)*12 = 6*\sqrt{3}\) But AD is given to be 6.
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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12 Apr 2015, 17:23
Main take away from this question is: Figures are not drawn to scale.rest explanations are already given.
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what is the area of triangular region [#permalink]
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08 Jun 2015, 10:29
If AD is 6 , and ADC is a right angle, what is the area of triangular region ABC? (1) Angle ABD = 60° (2) AC = 12
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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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08 Jun 2015, 10:38



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Re: If AD is 6 and ADC is a right angle, what is the area of [#permalink]
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25 Oct 2016, 06:46
amitjash wrote: Attachment: Triangle.jpg If AD is 6 and ADC is a right angle, what is the area of triangular region ABC? (1) Angle ABD = 60° (2) AC = 12 I tried not to solve everything as it is a DS question... Area is equal to base x height / 2 AD is height, BC is the base. We need to find the value of BC. 1. since B is 60 degree, A in ABD is 30. we have 1 leg, and we know the property of 306090 right triangle we can find BD. but since we don't know whether AD divides BC in two equal parts, then we can't tell exactly whether we can find BC. 2. AC = 12. We can find DC. we are faced with the same problem  can't find BD. 1+2 we have BD and we have DC. we can find the answer. C




Re: If AD is 6 and ADC is a right angle, what is the area of
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