11 dan 12 atau 1 aja dulu gpp Please bantu

11. AD = akar(BD × CD)
6akar(3) = akar(12 × CD)
36 × 3 = 12 × CD
CD = 36 × 3/12
CD = 9 cm (A)

12. SQ/QR = QT/PQ
8/(9 + RT) = 9/16
8 × 16 = 9(9 + RT)
8 × 16 = 81 + 9RT
128 = 81 + 9RT
9RT = 128 - 81
9RT = 47
RT = 47/9
RT = 5 2/9 (B)