Question 5903
25x^2+16<40x
25x^2-40x+16<0
(5x-4)^2<0  
Sqrt{(5x-4)^2}< Sqrt(0)
Abs(5x-4)< abs(0)
Abs(5x-4)< 0

there is no solution (all Abs must be 0 or bigger)