Respuesta :
Answer:
56x³+87x²+51x+27
Step-by-step explanation:
You have to do box method. Draw a box that 3 by 2 cubes long. On the side that is 3 cubes long. Write 7x² on top of the first cube, 3x on top of the second cube, and 3 on top of the third cube. On the side that is two cubes long, write 8x next to the first cube and 9 next to the second cube.