The angles of a triangle are , and . Prove that inside this triangle there exists a point that is located on the median through one vertex, the angle bisector through another vertex and the altitude through the third vertex.
Solutions — 3
Solution 1
Let be the point of intersection of and median from vertex , be the point of intersection of angle bisector from vertex and , and be the point of intersection of altitude from vertex and (see fig. 6). As and , triangle is a right isosceles triangle with .

Figure 6
Let and be the points of intersection of the line that passes through point and is parallel to , with lines and , respectively. We have , and . Therefore
due to which .
As line segments and are parallel, is the midsegment of triangle . Hence
Let now be the point of intersection of and . The angle bisector property gives that , so , from which . Therefore also passes through , QED.


Figure 7
Solution 2
Similarly to the previous solution we pick triangle , mark points , and and show that . Additionally notice that , which gives .
Let now be a point on such that (see fig. 7). Then and , hence triangles and are
which gives . Thus . Therefore and Ceva's theorem gives that , and intersect in one point.
Solution 3
Similarly to first solution we choose triangle , mark points , , and and show that .
Let the points of intersection of with angle bisector and median be and , respectively. Let and and in addition let and . Let us show that , then . Using the similarity of triangles and , similarity of triangles and and similarity of triangles and , we get the equalities
which imply and . From equation we get , therefore .