Tolong Bantu Saya Mengerjakan Ini

Jawabannya adalah B. 17 cm

[tex] {ac}^{2} = {ab}^{2} + {bc}^{2} \\ = {12}^{2} + {9}^{2} \\ = 144 + 91 \\ = 225 \\ ac = \sqrt{225} = 15[/tex]
sekarang mencari ad
[tex] {ad}^{2} = {ac}^{2} + {cd}^{2} \\ = {15}^{2} + {8}^{2} \\ = 225 + 64 \\ = 289 \\ad = \sqrt{289} = 17[/tex]