Question

Given: circle k(O), diameter US, measure of arc RU=50, measure of arc UT=30

Answer 1

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.