a: \(2+\dfrac{3\left(x+5\right)}{8}>\dfrac{x-1}{4}\)
=>\(2+\dfrac{3}{8}x+\dfrac{15}{8}>\dfrac{1}{4}x-\dfrac{1}{4}\)
=>\(\dfrac{3}{8}x+\dfrac{31}{8}>\dfrac{1}{4}x-\dfrac{1}{4}\)
=>\(\dfrac{1}{8}x>-\dfrac{1}{4}-\dfrac{31}{8}=\dfrac{-33}{8}\)
=>x>-33
b: \(2x-x\left(2x+1\right)< =15-2x\left(x+2\right)\)
=>\(2x-2x^2-x< =15-2x^2-4x\)
=>x<=15-4x
=>5x<=15
=>x<=3