Tom N. answered 12/12/19
Strong proficiency in elementary and advanced mathematics
Divide each term by x2 to get lim x→∞ (30x/x2 +2/x2) /(x2/x2 +x/x2 -51/x2) which gives lim x→∞ (30/x +2/x2)/ (1+1/x -51/x2). Take the limit x→∞ gives (0+0)/(1+0-0) and the limit is 0. So y→0 when x→∞.