Answer:
The missing angle is 65°
Explanation:
For context, all triangles' angles will always add up to 180°. The outside angle of S is supplementary to the inside angle, so in order to find S:
180 - 153 = 27°
<TSU = 27°
S = 27°
U = 88°
As mentioned before, angles of triangles will add up to 180. In order to find the missing angle (?) we will add the other two sides and subtract them from 180.
27 + 88 = 115
180 - 115 = 65°