WAEC - Mathematics (1993 - No. 23)

Two chords PQ and RS of a circle when produced meet at K. If ∠KPS = 31^o and ∠PKR = 42^o, find ∠KQR

11^o

73^o

107^o

138^o

149^o

QPS - QRK = 31^o
QRK + RKQ + KQR = 180
31 + 42 + KQR = 180^o
KQR = 180 - 73 = 107^o