According to the given data we have the following:
XY=a+8 in length
YZ= is 3a-1 in lenght
Segment XZ=35
In order to calculate the value of x we would have to make the following calculation:
XY+YZ=35
a+8+3a-1=35
4a=35-7
4a=28
a=7
So, if a=7, therefore:
XY=7+8=15
YZ=3(7)-1=20