Please help if possible

[Stupified]

Hello! The question I'm about to ask is not actually my problem. I agreed to help a friend, and it turns out I have absolutely no idea what to do either. This friend is in pre-calculus, but from what I can tell, this looks more like a problem for this section.

I do not have the actual picture for the problem as I can't access my friend's online book, so I'll try to explain it as best I can.

The rectangle in the middle is actually a square with sides = 5.
The Hypotenuse of the triangle ABC is 15.
Angle EBD is congruent with angle FDC.

Find side BE and FC. (BE ≠ FC)

Can the law of sines be used to solve this problem? And if so, where do you begin?

 

[daon2]

The larger triangle and two smaller ones are all similar. So set up some ratios!

 

[Stupified]

The larger triangle and two smaller ones are all similar. So set up some ratios!

Could you perhaps help me with these ratios? It's been a long time since I've done a problem like this. Every time I set up the ratios, I end up with something like be = fc. Obviously I'm setting them up incorrectly.

 

[stapel]

Hello! The question I'm about to ask is not actually my problem. I agreed to help a friend, and it turns out I have absolutely no idea what to do either....

I have no idea where to begin with this problem.

Unfortunately, it is nearly impossible to assist somebody by going through a "translator" who doesn't actually "know the language". Kindly please have your friend reply to this thread with his/her thoughts, so we can begin to provide useful assistance. Thank you!

 

[Stupified]

Not again...:-?

Anyway, if you and your "friend?" are unfamiliar with the basics of similar right triangles,
then you both(?) need classroom help.


Try here for an example:
http://www.jimloy.com/puzz/ladder0.htm

I am very familiar with the basics, thank you. It was my friend who asked me to try the law of sines as that was supposedly what they had been doing in class. If that formula is not needed for this problem, then I retract my question.

I must say, for helpers, you seem to act rather condescending. Guess perhaps I'm reading into it wrong. My apologies.

 

[Stupified]

OK then...BUT you clearly stated that you had NO IDEA how to solve.
Also, did you bother to read "Read before posting"?

Go here: http://mathcentral.uregina.ca/QQ/database/QQ.09.07/s/adrian1.html

If you can't follow how to solve at that site, then what do you expect from us?

I understand that information. I've already reached the answer with that procedure; HOWEVER, that is not my question. I wanted to know if there is a method to solve this problem using the law of sines. I have absolutely no idea on where to begin if I were to use law of sines to solve this problem. Wouldn't be doing my friend much good if I showed her a method which is actually not the way the instructor desires this problem to be solved. I suppose the way I worded stuff in the opener was rather misleading/confusing. My apologies.

Anyways, all I require is a simple yes or no.

 

[Stupified]

[k +- SQRT(k^2 - 4ku^2)] / (2u) where k = u[u + SQRT(u^2 + c^2)]

Yes, those are the exact answers I received! Rounded to 3 decimal placed to get BE = 3.351 and CF = 7.460

And you're right, there's not much point in using the law of sines for this problem. I was hoping that maybe there was a rule or something that I may have overlooked, but it appears that isn't the case. I'm guessing that this was supposed to be a review problem for my friend. Found another site, and I think this one might be the easiest to demonstrate with:

http://jwilson.coe.uga.edu/emt725/Class/Head/EMT 725/Ladder and Box/ladder.html

That little formula is actually rather perfect! Can't guarantee my friend will understand, but it's worth a shot!

Thanks a lot for your time! Sorry for getting rather irritable. This question took more out of me than it should have. Anyways, I believe I have enough to go on to give a decent explanation.