Răspuns:
Explicație pas cu pas:
notam ;
AB=3k ; AC=4k
BC²=AB²+AC²=(3k)²+(4k)²=9k²+16k²=25k²
BC=√25k² =5k
P =AB+AC+BC
48 =3k+4k+5k =12k
k =4
AB=3*4 =12 cm
AC=4*4+16 cm
BC=5*4 =20cm
AB²=BD*BC
12²=BD*20
BD=144/20=7.2 cm
CD=BC-BD=20-7.2 =12.8 cm
AD²=BD*CD
AD²=7.2*12.8 =92.16
AD=√92.16 =9.6 cm