If the constant term in the binomial expansion of \( \left(\dfrac{x^{5/2}}{2}-\dfrac{4}{x^{l}}\right)^{9} \) is \( -84 \) and coefficient of \( x^{-3l} \) is \( 2^{\alpha}\beta \), where \( \beta<0 \) is an odd number, then \( |\alpha l-\beta| \) is equal to ________.
