A=aria triunmghiului
a)
A=9×12/2=54 cm
A=BC×AD/2 ⇒BC=2A/AD=2×54/7,2=15 cm
b)
A(ABC)=12×16/2=96 cm
A=BC×AD/2 ⇒BC=2A/AD=2×96/9,6=20 cm
c)
A(ABC)=25×12/2=150 cm
A=AB×AC/2 ⇒AB=2A/AC=2×150/20=15 cm
d)
A=AB×AC/2 ⇒AC=2A/AB=2×216/18=24 cm
A=BC×AD/2 ⇒BC=2A/AD=2×216/14,4=30 cm
e)
A=AB×AC/2 ⇒AB=2A/AC=2×384/24=32 cm
A=BC×AD/2 ⇒AD=2A/BC=2×384/40=19,2 cm
