Answer:
25
Step-by-step explanation:
Similar Triangles have proportional sides:
Side BA is proportional to YX
Side BC is proportional to YZ
Side AC is proportional to XZ
Now Triangle XYZ is a scaled down version of Triangle ABC. To find the scale factor of this change, we can divide the proportional sides together.
10/2 = 5 and 15/3 = 5
Therefore the 5 scale factor.
So all you have to do is multiply 5 by 5 (25) and you will get the missing side BC :)
