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## #1 2013-04-30 09:08:32

cooljackiec
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### triangles!!!

Triangle ABC is a right triangle with right angle at A. Suppose AX is an altitude of the triangle, AY is an angle bisector of the triangle, and  AZ is a median of the triangle, and angle XAY=13. If X  is on BY, then what is the measure of angle ZAC?

I see you have graph paper.
You must be plotting something

## #2 2013-04-30 17:38:53

bob bundy
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### Re: triangles!!!

hi cooljackiec

I assumed that Y and Z are on the line BC.

Because Z is the midpoint of BC and there is a right angle at A, Z is the circumcentre of ABC.  ie.  A circle centred on Z will go through A, B and C.

So ZA = ZC and ZAC is isosceles.

So work oiut angles in this order:

XAY
XYA
YAC
ZCA (= YCA)
ZAC

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #3 2013-04-30 20:55:04

anonimnystefy
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### Re: triangles!!!

An alternative way to work it out is:
XAY
YAB
XAB
XBA
ZAC (=ZCA)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #4 2013-05-01 08:54:02

cooljackiec
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### Re: triangles!!!

oh yea, isoceles triangles! median of hypotenuse = half of hyptenuse. i get it

I got 32. not sure, this seems incorrect

Last edited by cooljackiec (2013-05-01 09:24:27)

I see you have graph paper.
You must be plotting something

## #5 2013-05-01 17:02:13

bob bundy
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### Re: triangles!!!

That's good.  32 is my answer too.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei