Question

what is m∠stu?
write your answer as an integer or decimal.
m∠stu = °

Explanation:

Step1: Find arc SU measure

The sum of central angles in a circle is $360^\circ$.
$$m\overset{\frown}{SU}=360^\circ - 127^\circ - 128^\circ=105^\circ$$

Step2: Calculate inscribed angle ∠STU

An inscribed angle is half its intercepted arc.
$$m\angle STU=\frac{1}{2}m\overset{\frown}{SU}$$
$$m\angle STU=\frac{1}{2}\times105^\circ=52.5^\circ$$

Answer:

$52.5$