Answer:
90
Step-by-step explanation:
There is no picture for me to check
You've already correctly labeled everything you need.
-- Ignore the lines YZ and YT .
-- That leaves you with the right triangle XYW .
-- Its legs are 8 and (12+3) = 15 .
-- XY is its hypotenuse.
I'm SURE you can finish it off from here.