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karthikpandian19
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Triangle Iso
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
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anandhimanshu85
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LalaB
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one more approach -
remember-the measure of an exterior angle equals the sum of its two non-adjacent interior angles
below (<) means angle
so,<BAD+<ABD=<BDC or x+<ABD=2x => <ABD=x
so, we the triangle ABD is isosceles. from the q. stem we can see, that the triangle BDC is also isosceles
so, from the stmnt 1 -AD=6 ,so AD=BD=BC=6
stmnt 2 is insuff,since there is no info about any side of the triangles
remember-the measure of an exterior angle equals the sum of its two non-adjacent interior angles
below (<) means angle
so,<BAD+<ABD=<BDC or x+<ABD=2x => <ABD=x
so, we the triangle ABD is isosceles. from the q. stem we can see, that the triangle BDC is also isosceles
so, from the stmnt 1 -AD=6 ,so AD=BD=BC=6
stmnt 2 is insuff,since there is no info about any side of the triangles
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GMATGuruNY
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To determine how the angles affect each other, PLUG IN.
What is the length of side BC?
1. AD = 6
2. x = 36
Just be sure to:
-- Satisfy the conditions given in the problem.
-- Satisfy the rules of geometry (the sum of the angles inside a triangle must be 180, etc.).
The result is the following:
The values in the figure above show that ∠ABD = ∠DAB.
Thus, AD = BD = BC.
Question rephrased: What is the length of AD or BD?
Statement 1: AD = 6
SUFFICIENT.
Statement 2: x=36
No information about any of the lengths.
INSUFFICIENT.
The correct answer is A.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
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ArunangsuSahu
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