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timothy.shaha
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(GMAT questions always have 5 answer choices).Sorry, but proofs aren't part of the GMAT.
Cheers,
Brent
Geometry
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Brent@GMATPrepNow
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A proof? What are the 5 answer choices (GMAT questions always have 5 answer choices).
Sorry, but proofs aren't part of the GMAT.
Cheers,
Brent
(GMAT questions always have 5 answer choices).Sorry, but proofs aren't part of the GMAT.
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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Lifetron
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I think, it has got to do with in-radius and circum-radius. They will divide the altitude in the ratio 1:2. Not sure, which is what though.The radius of a circle inside an equilateral triangle is one third the altitude of the triangle
Is the statement right ?
Atleast, we can use that for problems !
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timothy.shaha
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At least thank you for your concern. I honestly did't know that you can't
that my question is irrelevant.
that my question is irrelevant.
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veenu08
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Property of equilateral triangle-1.All centroid, circum centre, in center meet are concurrent
2. Centroid divide the median in 2:1 ratio
In equilateral triangle length of median(altitude)- (sqrt3)/2
Using point 2, the radius of incircle will be 1/3(altitude)
Hope this clears your doubt
2. Centroid divide the median in 2:1 ratio
In equilateral triangle length of median(altitude)- (sqrt3)/2
Using point 2, the radius of incircle will be 1/3(altitude)
Hope this clears your doubt
GMAT/MBA Expert
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Brent@GMATPrepNow
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In case any of this comes in handy, here's the proof:timothy.shaha wrote:How can I prove that the radius of a circle inside an equilateral triangle is one third the altitude of the triangle? Please Help Me.....
Start with this.
Draw line that bisects 60-degree angle to create 30-degree angle
Draw line from center to point of tangency to create 90-degree angle
IMPORTANT: This creates a special 30-60-90 triangle. So. let's let the radius of the circle have length 1
This means that the hypotenuse of the 30-60-90 triangle will have length 2
Finally, we can add another radius of length 1 to show that the equilateral triangle's altitude is 3 times the radius of the inscribed triangle.
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
