WAEC - Mathematics (2018 - No. 38)
In the diagram, PS and RS are tangents to the circle centre O. ∠PSR = 70°, ∠POR = m, and ∠PSR =n. Find ( m + n ).
110\(^o\)
135\(^o\)
165\(^o\)
225\(^o\)
คำอธิบาย
In the diagram,
Thus, m = 2 x 55\(^o\) (is a bisector of obtuse
m = 110\(^o\)
n = \(\frac{1}{2}\) x 110\(^o\) (angle at centre = 2 x angle at circum)
n = 55\(^o\)
m + n = 110 + 55 = 165\(^o\)