If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
(1) Angle ABD = 60°
(2) AC = 12
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In statement (1) ABD=60 tells you only ABD=60, how can you know that ACD is 60, 70 or even ...LazySammy wrote:I think the answer is C. Both statements together are sufficient. The area of of Equilateral triangle is S^2 sqrt(3) /4.
Given ABD is 60 tells you that this is an equilateral triangle.
Given AC = 12 helps you calculate area using the formula.
This is my best explanation. Let me know if this is right answer.
Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
LazySammy wrote:A. Since Angle ABD = 60 we can imply that ABC is an equilateral triangle because Angle ADB = 90 , Angle BAD = 30
and thus DAB is also equal to 30
We know that AD = 6 sqrt (3) and because ADB is a 30-60-90 Triangle the sides are in the ratio of 1 : sqrt (3) : 2 using this we can tell that AB = 12 , BD = 6 and AD = 6 sqrt (3) (given)
In an equilateral triangle since all sides are equal AB = AC = BC = 12 and given BD = 6 , DC = 6. With these dimensions and AD = 6 sqrt (3) we can find the area of the triangle. Sufficient.
B. AC = 12 and AD = 6 SQRT (3) we can find out DC = 6. Now working backwards since the ratios of the sides are in the ration of 1:sqrt 3 : 2 we can say Angle C = 60 and still be able to derive the area by using logic from A above.
Answer is D. Each stmt alone is sufficient.
Let me know what you think.
rohu27 wrote:1)angle ABD=60, so triangle ABD is a 30-60-90. we can find all the sides.(1:sqrt3:2) but we still dnt knw DC. so insuff.
2) AC=12, we can find DC
using 1 & 2 area = 1/2 bh.
so answer is C
Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
Pls post the OA.[/b]Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
ops, I just went through CAT Mgmat haven't seen OA yetankur.agrawal wrote:Pls post the OA.[/b]Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
Night reader wrote:st(1) we can find only two sides AB and BDrohu27 wrote:1)angle ABD=60, so triangle ABD is a 30-60-90. we can find all the sides.(1:sqrt3:2) but we still dnt knw DC. so insuff.
2) AC=12, we can find DC
using 1 & 2 area = 1/2 bh.
so answer is C
Night reader wrote:If AD is 6*SQRT(3), and ADC is a right angle, what is the area of triangular region ABC?
(1) Angle ABD = 60°
(2) AC = 12
irrelevant ---> angle ADC can be 90` when it is made by the line segments drawn from the points A-D-C as perpendiculars. The line segments should cross, and the line segment BC is placed on a cross-point.vaflaly wrote:To solve the question, we must assume that C, D, B are in the same line. Otherwise, the answer is E
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