Let the equation of plane passing through the line of intersection of the planes \( x+2y+az=2 \) and \( x-y+z=3 \) be \( 5x-11y+bz=6a-1 \). For \( c\in \mathbb{Z} \), if the distance of this plane from the point \( (a,-c,c) \) is \( \dfrac{2}{\sqrt{a}} \) then \( \dfrac{a+b}{c} \) is equal to:
