Question

Could anyone help me solve this Geometry-related triangle proof?
http://bit.ly/UoCydu

In the problem, the 3 line segments are congruent to the corresponding part in the other triangle.

Answer 1

I was thinking that you could do something by proving that the triangles are congruent by SSS and I'm pretty sure you have to use the Isosceles triangle theorem here.

Answer 2

well we know both triangle have 90 degrees as congruent angle. they also have 2 sides so they must be similar (congruent...)

Answer 3

How do we know they have 90 degrees? We can't look at things to scale.

Answer 4

im pretty sure that if you use the law of sines you will get that the triangles have the same angle

Answer 5

I don't have knowledge about that. If you look at the diagram it's pretty clear that it is isosceles, I just have no idea how to get to it.

Answer 6

well you just said you couldn't look at the triangles to scale so how can you possibly tell me that it clearly look like an isosceles triangle? then my assumption of 90 degrees is justified since it certainly looks as though the triangles are right ones.

Answer 7

I don't think you see what I am saying. With the knowledge that the two triangles are congruent and the way the points intersect, you can see how they are isosceles. The proof is asking you to prove it anyway. With the 90 degrees thing, no you can't guess a measure of an angle just by looking at it, that would be false.