a)
AC^2 =BC*DC
27^2 =BC*16.2
729 =BC*16.2
BC =729: 16.2 =45 cm
BD=BC-DC
BD =45-16.2 =28.8 cm
AB^2 =BC^2-AC^2
AB^2 =45^2-27^2
AB^2 =2025-729 =1296
AB = radic> din 1296 =36 cm
b)
B C =BD+DC
BC=27+48 =75 cm
AB^2=BC*DC
AB^2 =75*27 =2025
AB = rad 2025 =45 cm
AC^2 =BC*DC
AC^2 =75*48 =3600
AC = rad. 3600 =60 cm