Answer: 128 degrees
Step-by-step explanation
Interior angles R and Q have the same angle marker. The two angles are congruent. Both are (5x-4) degrees each.
We'll use the remote interior angle theorem to add those angles to get the exterior angle RST. Notice how neither Q nor R is adjacent to exterior angle RST.
Q + R = angle RST
(5x-4) + (5x-4) = 8x+4
10x-8 = 8x+4
10x-8x = 4+8
2x = 12
x = 12/2
x = 6
Then,
angle RST = 8*x+4 = 8*6+4 = 52 degrees
angle RSQ = 180 - (angle RST) = 180-52 = 128 degrees