Observe the figure below.
When two lines intersect each other, vertically opposite angles are always equal.
So,

![[11(y-10)]^\circ = (4y-5)^\circ](https://img.qammunity.org/2018/formulas/mathematics/high-school/9mvu9dr0p76ov6g9c8eo2nlc1m01i1teks.png)
![[11y-110]^\circ = (4y-5)^\circ](https://img.qammunity.org/2018/formulas/mathematics/high-school/iee2jqu80y90qjwqyaxvn6ke7j0s0dambm.png)
![[11y-4y]^\circ = (110-5)^\circ](https://img.qammunity.org/2018/formulas/mathematics/high-school/spn2071drdyc3lavlobkc9sok4rjwtmeuw.png)


So, the measure of 'y' is 15 degrees.
The measure of angle PTS = 11(y-10)
= 11(15-10)
= 55 degrees
So, the measure of angle PTS is 55 degrees.