AD=√[15²-12²]=9,BD=√[20²-12²]=16===>AB=9+16=25
EB/AE=BC/AC=20/15=4/3===>EB=25*4/7=100/7
∴DE=BD-BE=16-100/7=12/7
∴CE²=12²+(12/7)²=(50*144)/49===>CE=60√2/7
AD=√[15²-12²]=9,BD=√[20²-12²]=16===>AB=9+16=25
EB/AE=BC/AC=20/15=4/3===>EB=25*4/7=100/7
∴DE=BD-BE=16-100/7=12/7
∴CE²=12²+(12/7)²=(50*144)/49===>CE=60√2/7