DE⊥AC
DE inaltime in triunghiul ADC
DE²=AE•EC
DE²12•48 = 576
DE = 24
DA²=AC²·AE
DA²=12·60=720
DA=12√5
AB²=AC²-BC²=60²-(12√5)²==3600-720=2880
AB=24√5
A-aria
A=AB·BC=24√5·12√5=1440
Sper ca te-amajutat