Answer:
angle RUS = 65 degrees
angle STU = 90 degrees
Step-by-step explanation:
(a) find angle RUS
Given arc RU = 50 degrees, so angle RSU = 50/2 = 25 degrees
Since US is the diameter,
angle URS is a right-angle.
Consider triangle RUS,
sum of angles of a triangle = 25+90+RUS = 180
solve for
RUS = 180 - 25 - 90 = 65 degrees.
(b) Find STU
All diameters span a right angle at the circumference,
since we're given US is a diameter, this means that
angle STU is a right angle.
