6.
Intersecting chords:
RT x ST = PT x TQ
2 x 6 = 3 x TQ
12 = 3TQ
TQ = 12/3
TQ = 4
7.
AD = 90 -BE = 90-18 = 72
ADE = 180. DE = 180 - AD = 180-72 = 108
AE = 180. AB = 180-18 = 162
DE = 108
BD = BE +DE = 18 + 108 = 126
DAB = 72 + 162 = 234
ADE = 90 degrees
8.
AB^2 = BC* (BC +x)
8^2 = 2 * (2 +x)
64 = 4 + 2x
60 = 2x
X = 60/2
X = 30