In the diagram, ST//PQ reflex angle SRQ = 198o and o. Find the value of y
Attached Figure / Diagram
A
18o
B
54o
C
87o
D
92o
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
R +198 = 360(angles at a point)
R = 360 - 198 = 162o
C = 72(alternate angle), b + c = 180(angles or straight line)
b = 190 - c = 180 - 72 = 108
a + b = R = 162
a = R - b = 162 - 108
= 54, but a = y(alternate angles)
y = 54o
Source: Myschool Past Questions Archive (Record #36929)