JAMB - Mathematics (2017 - No. 13)

Given the quadrilateral RSTO inscribed in the circle with O as centre. Find the size angle x and given RST = 60^o

100^o

140^o

120^o

10^o

If RST = 60^o

RXT = 2 × RST

(angle at the centre twice angle at the circumference)

RXT = 2 × 60

= 120^o