Question 1085117
.
Use the fact that

<pre>
    in a triangle, the angle bisector divides the side to which it is drawn, in two segments proportional to the ratio of two other sides of a triangle. 
</pre>

For the proof, see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=>On what segments the angle bisector divides the side of a triangle</A>

in this site. 



Also, &nbsp;you have this free of charge online textbook on Geometry

&nbsp;&nbsp;&nbsp;&nbsp;<A HREF=https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson>GEOMETRY - YOUR ONLINE TEXTBOOK</A> 

in this site.


The referred lessons are the part of this online textbook under the topic "<U>Properties of triangles</U>".