Nomer 4 dan 5 gimana caranya?

bismillah
4. AB = PQ
BC = QR
AC = PR

PQ = AB = 16 cm
PQ = 3x + 7 = 16 cm
3x = 16 - 7
3x = 9
x = 9/3
x = 3 cm (pilihan A)

5. AC = DC
FB = FE
EC = BC
AE = DB
AF = FD

DE = AB
AB = (AF + FB)
AB = (5 cm + FB)
AB = (5 cm + (FB = FE))
AB = (5 cm + FE)
AB = (5 cm + 3 cm) =
AB = 8 cm

AC = (AE + EC)
AC = (4 cm + 6 cm) =
AC = 10 cm

panjang DE + AC :
8 cm + 10 cm =
18 cm (pilihan A)
maaf kalau salah