The graph of $y=\frac{5x^2-9}{3x^2+5x+2}$ has a horizontal asymptote at $y=a$. What is $a$?

The  horizontal asymptote  is

y  = ratio  of [ coefficient on x^2 in numerator  / coefficient on x^2 in denominator  ] = 

y  = a   = 5 / 3