Answer
EC=4
DC=12
Work Step by Step
EC(DC-EC)=AE(EB)
EC(16-EC)=8(6)
16EC-EC$^2$=48
EC$^2$-16EC+48=0
(EC-12)(EC-4)=0
Since EC appears shorter in the figure we'll say EC=4 which means DE=12.
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