# Thread: Vector proofs for triangles

1. ## Vector proofs for triangles

Prove that the internal bisectors of a triangle are concurrent.

I found the vectors for the angle bisectors of the triangle, and their sum is equal to 0, does this mean then that the lines are concurrent?

I have another question similar, asking me to prove that the perpendicular bisectors of a triangle are concurrent, I think its about the same.
Thanks

2. If the sum of three vectors is zero, either they form a triangle or they are cuncurrent.