若等边△ABC内一点到三边的距离分别为6,8,10,则△ABC的面积为( ) A.1903 B.1923 C.1943 D.1963
问题描述:
若等边△ABC内一点到三边的距离分别为6,8,10,则△ABC的面积为( )
A. 190
3
B. 192
3
C. 194
3
D. 196
3
答
设等边△ABC的边长是2a,连接OA,OB,OC,过A作AH⊥BC于H,则:BH=CH=a,由勾股定理得:AH=(2a)2−a2=3a,∵S△ABC=S△OBC+S△OAB+S△OAC,∴12•2a•3a=12•2a•6+12•2a•8+12•2a•10,解得:a=83,∴△ABC的面积...