WAEC - Mathematics (2009 - No. 42)
in the diagram, angle 20º is subtended at the centre of the circle, find the value of x
30o
50o
80o
100o
คำอธิบาย
2(30 + x) = 360 - 200
60 + 2x = 160
2x = 160 - 60
2x = 100
x = \(\frac{100}{2}\)
x = 50