从A作线AD⊥BC于D,则sinC=AD/AC,由sinB=sinC得AC=BC=b=c,△ABC的高AD=AC·sinC,则AD=bsinC=asinC;△ABC面积=15√3=1/2·AD·BC=1/2·bsinC·a,而ab=60√3:所以△ABC面积1/2sinC·ab=1/2sinC·60√3=sinC30√3=15√3,...