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Old 11-11-2008, 09:03 AM
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Default Isosceles triangle

in triangle ABC, AD and DC are angle bisectors and <B=76 What is the measure of <ADC

So I have a Triangle that is ABC, Angle A is Bisected by AD
Angle C is Bisected By DC
The meet at a point C in the triangle

I am told that B is 76 degrees, Since A and C are bisected I have a triangle ADC and I want the measure of D.

If I find the measure of angle BCA and BAC, take half of those and subtract from 180 that will give me angle D, But if I am not told that
triangle ABC is isosceles how can I conclude the measure of angle BCA and BAC, with the information that I am given that is the only way to find the angle. So advise would be great, sorry I dont have a picture



This is like the image that I have, where the internal point that the two intersect is D and the Three other vertex are A,B,C, Thanks

using paint I cant get it to copy and paste or insert the image.

Last edited by IDontunderstand; 11-11-2008 at 01:42 PM. Reason: Edit typo
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Old 11-11-2008, 11:41 AM
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Originally Posted by IDontunderstand View Post
In triangle ABC, AD and DE are angle bisectors and <=76 What is the measure of <ADC. If AD bisects angle A, what angle does DE bisect?

So I have a Triangle that is ABC, Angle A is Bisected by AD
Angle C is Bisected By CD. Angle C cannot possibly be bisected by CD.

I am told that B is 76 degrees, Since A and C are bisected I have a triangle ACD and I want the measure of D. There are two angles at D.

If I find the measure of angle BCA and BAC, take half of those and subtract from 180 that will give me angle D, But if I am not told that
triangle ABC is isosceles how can I conclude the measure of angle BCA and BAC, with the information that I am given that is the only way to find the angle. So advise would be great, sorry I dont have a picture
Use microsoft Paint and draw a picture. Your description tells an impossible story.
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