I need help on finding m

Answer:
39°
Step-by-step explanation:
[tex]\angle RUS +\angle SUT = \angle RUT\\\\5x-4+3x+6 = 90\\\\8x+2=90\\\\8x=88\\\\x=11[/tex]
and now for SUT
[tex]\angle SUT = 3(11)+6= 33+6 = 39[/tex]
angle RUT=90° ( angle of rectangle)
angle SUT+angle RUS=angle RUT
3x+6+5x-4=90
8x+2=90
8x=88
x=11
angle SUT =39°