t=90 because:
first, solve for other variables
(131)2+y*2=360 vertical angles are equal
y= 49, then solve for x,
x=180-73-42
x= 65
another side is 66 in x triangle.
then find the vertical angle between the z and the t triangle,
73+66+t triangle side= 180
t triangle side =41
49+41+t=180
t=90