we know that
If two figures are similar, then the ratio of its corresponding sides is proportional and its corresponding angles are congruent
In this problem
Verify if the corresponding sides are proportional
so
60/45=40/30=50/37.5
1.33=1.33=1.33 ------> is true
that means
the triangles are similar by SSS similarity theorem
so
the corresponding sides are
BC and XZ
AC and XY
AB and YZ
therefore
triangle ABC is similar to triangle YZX