In the diagram, o, o and o. Calculate the obtuse angle QRS.
- A.
90o - B.
100o - C.
121o - D.
60o
Correct Answer: Option C
Explanation
Joining SQ. In (bigtriangleup) SPQ,
(22o + a) + 55o + (41o + b) = 180o
121o + a + b = 180o
a + b = 180 – 121
a + b = 59o…..(1)
In (bigtriangleup) SRPQ; R + a + b = 180o
R + 59o = 180o
(in (1), a + b = 59o)
R = 180 – 59
R = 121o