Tolong banget kawan, plisss

30.
3 * 13 + 6 * 7 / 3 + 6 = 39 + 42 / 9 = 81 / 9 = 9 cm (D)

31. AD pangkat 2 = 16 x 9
AD kuadrat = 144
AD = 12 cm (B)

30).
EF=[AB.ED+DC.AE]÷[ED+AE]
EF=[13.3+7.6]÷[3+6]
EF=[39+42]÷[9]
EF=[81]÷9= 9 cm
31).
AD²=BD. DC
AD²=16.9
AD²=144
AD=√144=12 cm