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ABC is an equilateral triangle with point D on line BC such that AD =

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amanvermagmat
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ABC is an equilateral triangle with point D on line BC such that AD = [#permalink] New post   17 Jul 2018, 23:22
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ABC is an equilateral triangle with point D on line BC such that AD = 4 units. What is the area of triangle ABC in square units?

(1) AD is perpendicular to BC.

(2) D is mid point of BC.
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D
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chetan2u
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Re: ABC is an equilateral triangle with point D on line BC such that AD = [#permalink] New post   18 Jul 2018, 00:09
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ABC is an equilateral triangle with point D on line BC such that AD = 4 units. What is the area of triangle ABC in square units?

Look at the attached figure. In \(\triangle{ADB}\), we know one side and one angle thus the triangle can be of any size. so if we know ANY angle or ANY side, we can find all the sides as the triangle will be unique

(1) AD is perpendicular to BC.
If AD is perpendicular, AD is altitude and we can find sides and thus area of triangle
AD=4=\(side*\sqrt{3}/2\)
you can find side and thus area..
suff

(2) D is mid point of BC.
D is a midpoint means it is also perpendicular bisector
same as above
suff

D
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baraa900
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Re: ABC is an equilateral triangle with point D on line BC such that AD = [#permalink] New post   25 Nov 2020, 10:44
chetan2u wrote:
ABC is an equilateral triangle with point D on line BC such that AD = 4 units. What is the area of triangle ABC in square units?

Look at the attached figure. In \(\triangle{ADB}\), we know one side and one angle thus the triangle can be of any size. so if we know ANY angle or ANY side, we can find all the sides as the triangle will be unique

(1) AD is perpendicular to BC.
If AD is perpendicular, AD is altitude and we can find sides and thus area of triangle
AD=4=\(side*\sqrt{3}/2\)
you can find side and thus area..
suff

(2) D is mid point of BC.
D is a midpoint means it is also perpendicular bisector
same as above
suff

D

so we should estimate side*root3/2=4 to get the side?
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CEdward
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Re: ABC is an equilateral triangle with point D on line BC such that AD = [#permalink] New post   16 Feb 2021, 23:47
baraa900 wrote:
chetan2u wrote:
ABC is an equilateral triangle with point D on line BC such that AD = 4 units. What is the area of triangle ABC in square units?

Look at the attached figure. In \(\triangle{ADB}\), we know one side and one angle thus the triangle can be of any size. so if we know ANY angle or ANY side, we can find all the sides as the triangle will be unique

(1) AD is perpendicular to BC.
If AD is perpendicular, AD is altitude and we can find sides and thus area of triangle
AD=4=\(side*\sqrt{3}/2\)
you can find side and thus area..
suff

(2) D is mid point of BC.
D is a midpoint means it is also perpendicular bisector
same as above
suff

D

so we should estimate side*root3/2=4 to get the side?


It's data sufficiency, you don't have to go that far.
GMAT Club Bot
gmatclubot
Re: ABC is an equilateral triangle with point D on line BC such that AD = [#permalink]
16 Feb 2021, 23:47
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Bunuel
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