Question 405787
DE = 8 because AE = 20, AD = 12, and DE = AE - AD.


Also, we have {{{AB/BC = AD/DE}}}, so {{{AB/BC = 12/8 = 3/2}}} and it follows that {{{3BC = 2AB}}}. AC = 16, so AB + BC = 16. Letting BC = 2x and AB = 3x, we have


5x = 16 --> x = 16/5, so BC = 32/5 = 6.4 and AB = 48/5 = 9.6.