Triangle Puzzle

OK my first theory was obviously flawed but heres a second attempt.

Label the DC BE intersect X
Assign a distance of 10 to BC
With this we can work out the distances of BX and CX
Now we can work out the distances of XE, CE, XD and BD
Using the distance of XE, XD and angle DXE (70) we can solve the CDE angle.

29.999999999997772

Can the poster tell me if this is the right answer??

Originally posted by timebombted
Label the DC BE intersect X
Assign a distance of 10 to BC
With this we can work out the distances of BX and CX
Now we can work out the distances of XE, CE, XD and BD
Using the distance of XE, XD and angle DXE (70) we can solve the CDE angle.

How about this? Since I can't look at your math, how about you assign the values 5 and 15 to BC and see if you get the same answer? Then try assigning the value "x" to it and see if you can get it to cancel out with the same ~30 degree answer. If you could show your math in the post, it would be very helpful.

The reason I ask this is because I am not coming up with 30, or anything, assigning a precise value or not, and I would like to see your process.

If you don't come up with the same answer, then please post that you didn't, so we don't go crazy trying to make something work which is flawed.

Nemesio

At work no time to type up all paper calc's, although just tried it with 5 as the BC distance and still same answer........

Perhaps you could simply explain what process you used.

Lord people! I told you the answer was 30 degrees on page 1 of this post.

Please explain how you came to this conclusion. Anyone can say "The answer is x," but this has no meaning without a proof. It's not like figuring out a logic puzzle, geometry is drawing conclusions though a series conclusively true statements. Saying an answer without a proof does not demonstrate understanding of the problem.

So I ask again: Why do you believe the answer is 30 degrees and not 35 or 25 (etc.)?

Originally posted by nemesio
[b]Please explain how you came to this conclusion. Anyone can say "The answer is x," but this has no meaning without a proof. It's not like figuring out a logic puzzle, geometry is drawing conclusions though a series conclusively true statements. Saying an answer without a proof does not demonstrate understanding of the problem.

I would say getting the correct answer demonstrates an understanding of the problem! Get over yourself Nemesio, why should everyone have to justify themselves to you. As long as you can obtain 3 pieces of information out of 6 (which we do in this case after a few other calculations.....DX,EX and angle DXE) you can calculate the other angles CDE and BED.

Question for Ghost - Did you get exactly 30 degrees or have you rounded to this number?

Originally posted by timebombted
I would say getting the correct answer demonstrates an understanding of the problem!

SUBTANTIAL REEDIT: My apologies, as a large portion of my post got cut without my noticing.

Well, given that you applied a totally ineffective means of deducing the problem the first time, it seems very reasonable to question you when you say "The answer is 30" and give no substantiation of that answer.

You aren't proving it to ME so to speak but to the community here interested in this problem. We read this thread for the challenge, but also to learn new ways of thinking. Finding out only the answer without knowing how that answer was obtained does nothing to further that goal. So, in the spirit of learning a little more about geometry, I ask you, kindly a third time: please show us how you came to that conclusion of CDE=30 degrees [I had in error wrote DXE without looking at my diagram; of course DXE=70]. Thank you.

Nemesio

Agree my first method was crap - trying to take a huge short cut, but I think that only works with Eq Triangles (not tested so dont go off on one quoting me on that statement).

If the original poster tells me whether I'm right then I might bother to post all the calcs but hey I might still be wrong which makes it all a waste of my time. Until then I have told you where I started and which bits of info this enables me to obtain, so do the calcs yourself, cause I dont have to prove jack to YOU boy.

Nemesio

Think you'll also find DXE is 70 degrees...... or do I have to provide my workings to explain that angles on a straight line total 180 degrees?

180 - 110 = 70

Originally posted by timebombted
Until then I have told you where I started and which bits of info this enables me to obtain, so do the calcs yourself, cause I dont have to prove jack to YOU boy.

Here is the difference between you and me. I am interested in understanding the problem, irrespective of whether or not I solved it by myself or with the help of others. I am interested in the pursuit of knowledge.

You are interested in competition where you are the "man" (as opposed to me the "boy" as you say) because you solved this puzzle, a post on RHP. It's kind of sad, actually, and if the puzzle means that much to you, I concede that you are the man.

May I have a piece of that manhood by seeing the proof which I, in my immature boyhood, was unable to deduce by myself.

It is my personal belief, however, that you are loath to reveal your method for fear of being emasculated, again, on this thread, by a "boy."

Nemesio, humble boy

Originally posted by timebombted

Think you'll also find DXE is 70 degrees...... or do I have to provide my workings to explain that angles on a straight line total 180 degrees?

180 - 110 = 70[/b]

I don't know why you feel the great need to be rude about this, except trying to recover some face from your error previously posted by ruffling your feathers. Certainly we who are doing geometry puzzles are above reenacting the mating rituals of animals. I typed DXE in error without looking at my diagram; I, of course, meant CDE. DXE is, of course, easy to get. I apologize for my confusing post earlier, which was clipped by my error; you will see that it has been edited to accurately reflect what I was trying to say.

Nemesio, humble boy

Most things in life are a competition, unfortunately, and the puzzle forums are no different..... I agree its also a quest for knowledge and to challenge oneself. Clear your mind and the way forward will reveal itself.

But hey calm down fella, the ruffling of feathers can be passed in both directions....... so just see this for what it is..... harmless banter.

We still dont know if I'm right yet and I truely dont care if I'm wrong, if I am I will just give it another go.

Gotta go more mating rituals to re-enact :0)

Just so you dont spit the dummy any further Nemesio heres a brief use of my methodology :0)

After working out all possible angles through the 180 degrees in a triangle rule, 180 degrees on a straight line rule, Iso tri rules........

Start by assigning a distance of 10 to BC, using either your Cosine Rule or Sine Rule appropriately you can now start working your way up the figure until you have 2 sides and a non inclusive angle of triangle DXE. From memory when you first get this far you have angle dxe, side XE and side XD using the Cosine rule.......

c2=a2+b2-2abCosC

Gives you side DE.

Now using the Sine rule.......

a b
_ = _
SinA SinB

You can calculate CDE....... like I said still dont know if this is right, its just a theory that I wish the poster would say yay or nay to :0)

Originally posted by timebombted
like I said still dont know if this is right, its just a theory that I wish the poster would say yay or nay to :0)

Why should I do that when I am enjoying this thread so much? 😵

Your previous post, a triumph of form over content, could hardly be called a cogent argument.

And how come, given the iron logic of your solution, that you don't KNOW if your answer is correct or not?

.