Răspuns:
BC=50cm
CD=32cm
AC=800cm
AD=240cm
Explicație pas cu pas:
EX15:AB^2=BC×BD=>30^2=BC×18=>900=BC-18=>BC=900÷18=>BC=50
CD=BC-BD=>CD=50-18=>CD=32
AC^2=BC×DC=>AC^2=50×32=>AC^2=1600=>AC=1600÷2=>AC=800
AD^2=AB×AC/BC=>AD^2=30×800/50=>AD^2=24000/50=>AD^2=480=>AD=480÷2=>AD=240