In the diagram, PX is a tangent to the circle and RST is an equilateral triangle. Calculate < PTS
Attached Figure / Diagram
A
60o
B
90o
C
120o
D
150o
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
\(\bigtriangleup\) RST is equilateral triangle, hence
o
But o(Angle between a chord and a tangent at the point of contact = Angle in the alt. segment). From the diagram o + 60o = 120o
Source: Myschool Past Questions Archive (Record #36422)