I will mark brainlest please help!!!!

Answer:
m∠T = 45°
Step-by-step explanation:
The sum of angles in a triangle is 180°.
∠S + ∠T + ∠U = 180°
2x + 10 + 3x - 9 + 6x - 19 = 180
11x - 18 = 180
11x = 180 + 18
= 198
x = 198 ÷ 11
x = 18
m∠T = 3x - 9
= 3(18) - 9
= 54 - 9
m∠T = 45°