equilateral traingle

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equilateral traingle

by nidhis.1408 » Tue Nov 27, 2012 8:57 am
What is the length of side AB in equilateral triangle ABC if the length of altitude AD to side BC is 12?

1. 8√3
2. 10√2
3. 18
4. 12√3
5. 24

I need help with this problem.

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by nisagl750 » Tue Nov 27, 2012 9:33 am
nidhis.1408 wrote:What is the length of side AB in equilateral triangle ABC if the length of altitude AD to side BC is 12?

1. 8√3
2. 10√2
3. 18
4. 12√3
5. 24

I need help with this problem.
In an equilateral triangle, Altitude is (sqrt3 / 2) * side

Given, Altitude AD = 12
So, Side = 2/(sqrt3) *12

Answer choice 1

Image

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by nidhis.1408 » Tue Nov 27, 2012 10:17 am
is the altitude 12? the relationship given is AD/BC = 12.(altitude to side)
I still don't see the answer.

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by nisagl750 » Tue Nov 27, 2012 10:34 am
nidhis.1408 wrote:is the altitude 12? the relationship given is AD/BC = 12.(altitude to side)
Yes the altitude is 12.

Question says....Altitude AD (which is perpendicular to Side BC)

We can say Altitude AD to side BC which means AD is perpendicular to BC.
I still don't see the answer.
Just select that black portion or keep your mouse pointer on that......

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by Bill@VeritasPrep » Tue Nov 27, 2012 10:39 am
nidhis.1408 wrote:is the altitude 12? the relationship given is AD/BC = 12.(altitude to side)
I still don't see the answer.
I think it means that the altitude is from angle A to point D, which is on side BC. It's just poorly worded.
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