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Can't get the answer.

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- May 27th 2014, 08:43 PMkastamonucongruent triangles
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Can't get the answer. - May 28th 2014, 06:44 AMbjhopperRe: congruent triangles
- May 28th 2014, 07:02 AMkastamonuRe: congruent triangles
How?Which line do I have to draw?

- May 28th 2014, 08:18 AMPlatoRe: congruent triangles
- May 28th 2014, 08:43 AMbjhopperRe: congruent triangles
There is sufficient information to solve this problem. Answer is 63.4 degrees

- May 28th 2014, 08:44 AMkastamonuRe: congruent triangles
Yes I did. It has something to do with congruent triangles. We have to draw a line.

- May 28th 2014, 08:45 AMkastamonuRe: congruent triangles
Maybe we have to create an isosceles triangle. Angle is 40 degrees.

- May 28th 2014, 08:49 AMPlatoRe: congruent triangles
- May 28th 2014, 09:14 AMkastamonuRe: congruent triangles
It is in Turkish.

- May 28th 2014, 09:15 AMkastamonuRe: congruent triangles
I translated it word by word. I also sent a mail to the author.

- May 28th 2014, 09:27 AMkastamonuRe: congruent triangles
View image: kelebek2 here it is.

- May 28th 2014, 10:22 AMbjhopperRe: congruent triangles
My answer was based on angle ABE of 30 deg.If it is 40 deg I do not see a solution with out further info

- May 28th 2014, 01:45 PMbjhopperRe: congruent triangles
In further review I have come up with 79.3 degrees for the unknown angle When I drew a diagram I found that CD was very close to a side of the equilateral triangle and decided that the angle could be calculated

1 find the length of AE using 8 as a side of equilateral .Altitude of AEC and segments on AC calculate using angles of 20 and60

2 AD =AC +AD

3 Drop a perpendicular from D to AC extended.Mark F the intersection of same with AC ext

4 Angle DCF calculates fromDF and CF as 40.7

5 180-40.7-60= unknown =79.3 - May 28th 2014, 06:28 PMbjhopperRe: congruent triangles
in post 13 line number2 should read AD=AE +ED.Triangle ADF is a 20-70 rt triangle so length of DF and AF can be calculated from AD.CF is AF-8

- May 28th 2014, 09:50 PMkastamonuRe: congruent triangles
An swer is 80.But this is not a tri. question.If we can prove that CDE is isosceles....