如图 △ADC与△CDB相似CD:DB=AD:CD
AD=13 cd=6知道6:DB=13:6
DB=36/13
(ac+bc)^2=ac^2+bc^2+2ac*bc=AB^2+2CD*AB=AB(AB+2CD)
=(13+36/13)*(13+36/13 +12)
ac+bc=√(13+36/13)*(25+36/13) =√205*361/13=19√(205/13)
(字母没区分大小写 勿怪)
如图 △ADC与△CDB相似CD:DB=AD:CD
AD=13 cd=6知道6:DB=13:6
DB=36/13
(ac+bc)^2=ac^2+bc^2+2ac*bc=AB^2+2CD*AB=AB(AB+2CD)
=(13+36/13)*(13+36/13 +12)
ac+bc=√(13+36/13)*(25+36/13) =√205*361/13=19√(205/13)
(字母没区分大小写 勿怪)