$5x \times \left( 7{x}^{2}-12x+27 \right)-4y \times \left( 7{x}^{2}-12x+27 \right)$
Distribute $5x$ through the parentheses$35{x}^{3}-60{x}^{2}+135x-4y \times \left( 7{x}^{2}-12x+27 \right)$
Distribute $-4y$ through the parentheses$35{x}^{3}-60{x}^{2}+135x-28{x}^{2}y+48xy-108y$