$9{x}^{5}{y}^{-3}{z}^{7} \times \left( {x}^{0}{y}^{4}z \right)$
Any non-zero expression raised to the power of $0$ equals $1$$9{x}^{5}{y}^{-3}{z}^{7} \times \left( 1{y}^{4}z \right)$
Any expression multiplied by $1$ remains the same$9{x}^{5}{y}^{-3}{z}^{7} \times \left( {y}^{4}z \right)$
Remove unnecessary parentheses$9{x}^{5}{y}^{-3}{z}^{7}{y}^{4}z$
Calculate the product$9{x}^{5}y{z}^{8}$