Answer :
Simplifying
6x * 3y * 9x2y4
Reorder the terms for easier multiplication:
6 * 3 * 9x * y * x2y4
Multiply 6 * 3
18 * 9x * y * x2y4
Multiply 18 * 9
162x * y * x2y4
Multiply x * y
162xy * x2y4
Multiply xy * x2y4
162x3y5