how do you solve this i never got taught how to do this

Answer:
35°
Step-by-step explanation:
Angle UXW,
Firstly..always remember that a triangle's interior angles always add up to 180°,
Angle XUW is 90°
Then we make an equation,
; 55 + 90 + X(angle UXW) = 180
; 145 + X = 180
; Hence angle(UXW) = 180 - 145
; Angle(UXW) = 35°