Answer:
8 x^9y^4
Step-by-step explanation:
blank / 1/2 x^3 = 16x^6y^4
blank = 1/2 x^3 * 16 x^6 y^4
= 1/2 * 16 * x^3 x^6 y^4
= 8 x^(6+3) y^4
= 8 x^9y^4
